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在項目中有一個小功效須要完成，就是對多行文本停止排版結構，每行的內容又分為兩部門，右邊為題目，左邊為描寫，右邊內容長度不肯定，左邊的內容須要對齊，若有換行也須要對齊左邊的文本。
1、後果圖
可以看到內容分紅了兩部門，右邊的色彩與左邊紛歧致，左邊的描寫案牍同一對齊。
2、完成計劃
以上功效，因為輸出內容輸出行數不肯定，而且右邊的案牍長度也不肯定，是以不克不及直接在結構中完成，基於此這裡重要完成了以下6種方法
計劃1
采取自界說控件的方法，繼續TextView，從新onDraw函數，完成以下：
/**
* 盤算出右邊最長的顯示字符串maxLeftWidth，以後draw每行字符，左邊的描寫從maxLeftWidth開端draw
* 當一行顯示不完整時，折行而且空出maxLeftWidth的空格長度
*/
public class TypographyView1 extends TextView {
private Paint leftPaint = new Paint();
private Paint rightPaint = new Paint();
private int fullWidth;
private float textSize;
private JSONArray array;
private int middlePadding = 0;
float maxLeftWidth = 0;
int itemSize = 0;
public TypographyView1(Context context) {
super(context);
init();
}
public TypographyView1(Context context, AttributeSet attrs) {
super(context, attrs);
init();
}
public TypographyView1(Context context, AttributeSet attrs, int defStyleAttr) {
super(context, attrs, defStyleAttr);
init();
}
private void init() {
textSize = getResources().getDimensionPixelSize(R.dimen.text_size_13);
leftPaint.setAntiAlias(true);
leftPaint.setTextSize(textSize);
leftPaint.setColor(getResources().getColor(R.color.color_black_999999));
rightPaint.setAntiAlias(true);
rightPaint.setTextSize(textSize);
rightPaint.setColor(getResources().getColor(R.color.color_black));
middlePadding = getResources().getDimensionPixelSize(R.dimen.padding_value);
}
@Override
protected void onSizeChanged(int w, int h, int oldw, int oldh) {
super.onSizeChanged(w, h, oldw, oldh);
fullWidth = getWidth();// 全部textView的寬度
}
public void setText(JSONArray array) {
this.array = array;
if (array != null) {
try {
int size = itemSize = array.length();
for (int i = 0; i < size; ++i) {
JSONArray o = (JSONArray) array.get(i);
String key = o.getString(0);
String value = o.getString(1);
if (TextUtils.isEmpty(key) || TextUtils.isEmpty(value)) {
itemSize--;
continue;
}
float curWidth = leftPaint.measureText(key);
if (curWidth > maxLeftWidth) {
maxLeftWidth = curWidth;
}
}
maxLeftWidth = maxLeftWidth + middlePadding;
invalidate();
} catch (Exception e) {
}
}
}
boolean setHeight = false;
@Override
protected void onDraw(Canvas canvas) {
if (array == null) {
return;
}
int lineCount = 0;
try {
JSONArray item;
float offsetY;
for (int i = 0; i < itemSize; ++i) {
item = (JSONArray) array.get(i);
offsetY = (lineCount + 1) * textSize;
canvas.drawText(item.getString(0), 0, offsetY, leftPaint);
String value = item.getString(1);
float valueWidth = rightPaint.measureText(value);
if (valueWidth > fullWidth - maxLeftWidth) {// 一行顯示不完
char[] textCharArray = value.toCharArray();
float charWidth;
float drawWidth = maxLeftWidth;
for (int j = 0; j < textCharArray.length; j++) {
charWidth = rightPaint.measureText(textCharArray, j, 1);
if (fullWidth - drawWidth < charWidth) {
lineCount++;
drawWidth = maxLeftWidth;
offsetY += textSize;
}
canvas.drawText(textCharArray, j, 1, drawWidth, offsetY, rightPaint);
drawWidth += charWidth;
}
} else {
canvas.drawText(value, maxLeftWidth, offsetY, rightPaint);
}
lineCount += 2;
}
if (!setHeight) {
setHeight((lineCount + 1) * (int) textSize);
setHeight = true;
}
} catch (JSONException e) {
e.printStackTrace();
}
}
}
添加了setText(JSONArray array)作為數據輸出，而且在這外面丈量了右邊title的最年夜寬度，以後挪用invalidate觸發重繪，在onSizeChanged獲得全部控件的寬度，重繪會挪用onDraw函數，這裡不須要挪用super函數，TextView的onDraw函數做了異常多的操作，解析傳入的數據，分離一行一行挪用canvas來停止drawText操作，當繪制描寫時，先盤算寬度，假如跨越殘剩控件解釋須要換行，最初挪用setHeight設置高度，這個加一個斷定前提，由於會觸發requestLayout()停止從新結構和invalidate()停止重繪，假如不加斷定會一向重繪。
計劃2
方法2與方法1差不多，分歧為一切盤算都在onDraw函數中：
/**
* 該方法與方法1很相似，只是一切的盤算都放在了onDraw辦法中。
*/
public class TypographyView2 extends TextView {
private Paint paint1 = new Paint();
private Paint paint2 = new Paint();
private int middlePadding = 0;
int width;
private float textSize;
private JSONArray array;
public TypographyView2(Context context) {
super(context);
init();
}
public TypographyView2(Context context, AttributeSet attrs) {
super(context, attrs);
init();
}
public TypographyView2(Context context, AttributeSet attrs, int defStyleAttr) {
super(context, attrs, defStyleAttr);
init();
}
private void init() {
textSize = getResources().getDimensionPixelSize(R.dimen.text_size_13);
paint1.setAntiAlias(true);
paint1.setTextSize(textSize);
paint1.setColor(getResources().getColor(R.color.color_black_999999));
paint2.setAntiAlias(true);
paint2.setTextSize(textSize);
paint2.setColor(getResources().getColor(R.color.color_black));
middlePadding = getResources().getDimensionPixelSize(R.dimen.padding_value);
}
@Override
protected void onSizeChanged(int w, int h, int oldw, int oldh) {
super.onSizeChanged(w, h, oldw, oldh);
width = getWidth();// 全部textView的寬度
}
public void setText(JSONArray array) {
this.array = array;
if (array != null) {
invalidate();
}
}
boolean setHeight = false;
@Override
protected void onDraw(Canvas canvas) {
// super.onDraw(canvas);
int lineCount = 0;
int size = array.length();
float maxLeftWidth = 0;
float drawWidth = 0;
try {
for (int i = 0; i < size; ++i) {
JSONArray o = (JSONArray) array.get(i);
String key = o.getString(0);
float v = paint1.measureText(key);
if (v > maxLeftWidth) {
maxLeftWidth = v;
}
}
maxLeftWidth = maxLeftWidth + middlePadding;
for (int i = 0; i < size; ++i) {
JSONArray o = (JSONArray) array.get(i);
String key = o.getString(0);
canvas.drawText(key, 0, (lineCount + 1) * textSize, paint1);
String value = o.getString(1);
char[] textCharArray = value.toCharArray();
float charWidth;
drawWidth = maxLeftWidth;
for (int j = 0; j < textCharArray.length; j++) {
charWidth = paint1.measureText(textCharArray, j, 1);
if (width - drawWidth < charWidth) {
lineCount++;
drawWidth = maxLeftWidth;
}
canvas.drawText(textCharArray, j, 1, drawWidth, (lineCount + 1) * textSize, paint2);
drawWidth += charWidth;
}
lineCount += 2;
}
if (!setHeight) {
setHeight((lineCount + 1) * (int) textSize + 5);
setHeight = true;
}
} catch (JSONException e) {
e.printStackTrace();
}
}
}
該計劃的完成是不太好的，計劃1也是在此基本長進行調劑的，在這裡放出來只是為了解釋，一切的盤算不要全體放在onDraw外面，由於該辦法能夠會重復挪用屢次，如許就下降了機能。
計劃3
將數據源拼接成SpannableString，重寫onDraw函數，依據內容draw每個字符：
/**
* 該辦法，是須要顯示的內容先拼接成SpannableString，在onDraw辦法中獲得一切的char字符，一個一個比擬
* 當為分號是，表現為key與value的分隔符。
*/
public class TypographyView3 extends TextView {
private Paint leftPaint = new Paint();
private Paint rightPaint = new Paint();
int width;
private String text;
private float textSize;
float maxLeftWidth = 0;
private int middlePadding = 0;
public TypographyView3(Context context) {
super(context);
init();
}
public TypographyView3(Context context, AttributeSet attrs) {
super(context, attrs);
init();
}
public TypographyView3(Context context, AttributeSet attrs, int defStyleAttr) {
super(context, attrs, defStyleAttr);
init();
}
private void init() {
textSize = getResources().getDimensionPixelSize(R.dimen.text_size_13);
textSize = getResources().getDimensionPixelSize(R.dimen.text_size_13);
leftPaint.setAntiAlias(true);
leftPaint.setTextSize(textSize);
leftPaint.setColor(getResources().getColor(R.color.color_black_999999));
rightPaint.setAntiAlias(true);
rightPaint.setTextSize(textSize);
rightPaint.setColor(getResources().getColor(R.color.color_black));
middlePadding = getResources().getDimensionPixelSize(R.dimen.padding_value);
}
@Override
protected void onSizeChanged(int w, int h, int oldw, int oldh) {
super.onSizeChanged(w, h, oldw, oldh);
width = getWidth();// 全部textView的寬度
}
public void setText(JSONArray data) {
if (data == null) {
return;
}
try {
int size = data.length();
for (int i = 0; i < size; ++i) {
JSONArray o = (JSONArray) data.get(i);
String key = o.getString(0);
float v = leftPaint.measureText(key);
if (v > maxLeftWidth) {
maxLeftWidth = v;
}
}
maxLeftWidth += middlePadding;
SpannableStringBuilder ssb = new SpannableStringBuilder();
for (int i = 0; i < size; ++i) {
addItem((JSONArray) data.get(i), ssb, i != 0);
}
setText(ssb, BufferType.SPANNABLE);
} catch (Exception e) {
}
}
private void addItem(JSONArray item, SpannableStringBuilder ssb, boolean breakLine) {
try {
if (item == null || item.length() == 0) {
return;
}
String key = item.getString(0);
String value = (item.length() >= 2) ? item.getString(1) : "";
if (TextUtils.isEmpty(key) && TextUtils.isEmpty(value)) {
return;
}
if (breakLine) {// 換行
ssb.append("\r\n");
ssb.append("\r\n");
}
SpannableString span = new SpannableString(key);
// span.setSpan(new ForegroundColorSpan(getResources().getColor(R.color.colorAccent)), 0, key
// .length(),
// Spanned.SPAN_INCLUSIVE_EXCLUSIVE);
ssb.append(span);
ssb.append(value);
} catch (JSONException e) {
e.printStackTrace();
}
}
@Override
protected void onDraw(Canvas canvas) {
// super.onDraw(canvas);
int lineCount = 0;
text = this.getText().toString();
if (text == null)
return;
char[] textCharArray = text.toCharArray();
// 已繪的寬度
float drawWidth = 0;
float charWidth;
Paint paint = leftPaint;
for (int i = 0; i < textCharArray.length; i++) {
charWidth = leftPaint.measureText(textCharArray, i, 1);
if (textCharArray[i] == '\n') {
lineCount++;
drawWidth = 0;
paint = leftPaint;
continue;
}
if (width - drawWidth < charWidth) {
lineCount++;
drawWidth = maxLeftWidth;
}
if (i > 1 && textCharArray[i - 1] == ':') {
drawWidth = maxLeftWidth;
paint = rightPaint;
}
canvas.drawText(textCharArray, i, 1, drawWidth, (lineCount + 1) * textSize, paint);
drawWidth += charWidth;
}
//may be need set height
//setHeight((lineCount + 1) * (int) textSize + 5);
}
}
這裡先盤算右邊title的最年夜寬度，同時將一切的數據拼接成一個SpannableStringBuilder，挪用setText函數會觸發重繪，在onDraw函數中停止處置，因為未從新super函數，是以SpannableString的setSpan函數掉效，該計劃重要依據分隔符來停止朋分，是以分隔符須要獨一。
計劃4
采取GridLayout方法完成，然則原始控件有展現成績，是以對此停止了修正：
public class Typography4Activity extends BaseActivity {
public static void start(Context context) {
Intent intent = new Intent();
intent.setClass(context, Typography4Activity.class);
context.startActivity(intent);
}
private LinearLayout root;
private Paint leftPaint = new Paint();
private float textSize;
private float maxLeftWidth;
private int middlePadding = 0;
private float maxRightWidth;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
root = (LinearLayout) LayoutInflater.from(this).inflate(R.layout.activity_typography4, null);
setContentView(root);
initPaint();
findViews();
loadData();
}
private void initPaint() {
textSize = getResources().getDimensionPixelSize(R.dimen.text_size_13);
leftPaint.setAntiAlias(true);
leftPaint.setTextSize(textSize);
leftPaint.setColor(getResources().getColor(R.color.color_black_999999));
middlePadding = getResources().getDimensionPixelSize(R.dimen.padding_value);
}
private void findViews() {
}
private void loadData() {
addGridLayout(DataSource.getArray());
TextView view = new TextView(this);
view.setText("修正後的完成");
view.setGravity(Gravity.CENTER);
view.setLayoutParams(new ViewGroup.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT, 160));
root.addView(view);
addModifyGridLayout(DataSource.getArray());
}
private void addGridLayout(JSONArray data) {
try {
GridLayout layout = createGridLayout();
int size = data.length();
for (int i = 0; i < size; ++i) {
JSONArray item = (JSONArray) data.get(i);
String key = item.getString(0);
String value = (item.length() >= 2) ? item.getString(1) : "";
GridLayout.Spec row = GridLayout.spec(i);
GridLayout.Spec col1 = GridLayout.spec(0);
GridLayout.Spec col2 = GridLayout.spec(1);
GridLayout.LayoutParams params = new GridLayout.LayoutParams(row, col1);
TextView title = getLeftTextView(key);
layout.addView(title, params);
params = new GridLayout.LayoutParams(row, col2);
TextView desc = getRightTextView(value);
layout.addView(desc, params);
}
root.addView(layout);
} catch (Exception e) {
}
}
@NonNull
private TextView getRightTextView(String value) {
TextView desc = new TextView(this);
desc.setTextSize(13);
desc.setTextColor(getResources().getColor(R.color.black));
desc.setText(value);
return desc;
}
@NonNull
private TextView getLeftTextView(String key) {
TextView title = new TextView(this);
title.setText(key);
title.setPadding(0, middlePadding, middlePadding, 0);
title.setTextColor(getResources().getColor(R.color.color_black_999999));
title.setTextSize(13);
return title;
}
private void addModifyGridLayout(JSONArray data) {
try {
calculateLeftMaxWidth(data);
GridLayout layout = createGridLayout();
int size = data.length();
for (int i = 0; i < size; ++i) {
JSONArray item = (JSONArray) data.get(i);
GridLayout.Spec row = GridLayout.spec(i);
String key = item.getString(0);
GridLayout.Spec col1 = GridLayout.spec(0);
GridLayout.LayoutParams params = new GridLayout.LayoutParams(row, col1);
TextView title = getLeftTextView(key);
layout.addView(title, params);
String value = (item.length() >= 2) ? item.getString(1) : "";
GridLayout.Spec col2 = GridLayout.spec(1);
params = new GridLayout.LayoutParams(row, col2);
TextView desc = getRightTextView(value);
params.width = (int) maxRightWidth;
params.height = ViewGroup.LayoutParams.WRAP_CONTENT;
layout.addView(desc, params);
}
root.addView(layout);
} catch (Exception e) {
}
}
private void calculateLeftMaxWidth(JSONArray data) {
try {
DisplayUtil.init(this);// 這個可以在運用法式起來的時刻init
int size = data.length();
for (int i = 0; i < size; ++i) {
JSONArray o = (JSONArray) data.get(i);
String key = o.getString(0);
String value = o.getString(1);
if (TextUtils.isEmpty(key) || TextUtils.isEmpty(value)) {
continue;
}
float curWidth = leftPaint.measureText(key);
if (curWidth > maxLeftWidth) {
maxLeftWidth = curWidth;
}
}
maxLeftWidth = maxLeftWidth + middlePadding;
maxRightWidth = DisplayUtil.screenWidth - DisplayUtil.dp2px(this, 32 + 10) - maxLeftWidth;
} catch (Exception e) {
}
}
private GridLayout createGridLayout() {
GridLayout layout = new GridLayout(this);
layout.setColumnCount(2);
//layout.setRowCount(5);
layout.setOrientation(GridLayout.HORIZONTAL);
return layout;
}
}
假如直接創立一個GridLayout，外面添加每項，假如描寫太長都招致顯示不全，這個是體系的一個bug，盤算的寬度有成績，是以須要對此計劃停止更改。
更改方法為先盤算右邊占用的最年夜寬度，在添加左邊的項時，設置結構參數掌握最年夜的長度。
計劃5
采取每行一個結構，手動一行一行停止添加：
public class Typography5Activity extends BaseActivity {
public static void start(Context context) {
Intent intent = new Intent();
intent.setClass(context, Typography5Activity.class);
context.startActivity(intent);
}
private LinearLayout root;
private Paint leftPaint = new Paint();
private float textSize;
private float maxLeftWidth;
private int middlePadding = 0;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
root = (LinearLayout) LayoutInflater.from(this).inflate(R.layout.activity_typography5, null);
setContentView(root);
initPaint();
loadData();
}
private void initPaint() {
textSize = getResources().getDimensionPixelSize(R.dimen.text_size_13);
leftPaint.setAntiAlias(true);
leftPaint.setTextSize(textSize);
leftPaint.setColor(getResources().getColor(R.color.color_black_999999));
middlePadding = getResources().getDimensionPixelSize(R.dimen.padding_value);
}
private void loadData() {
JSONArray array = DataSource.getArray();
calculateLeftMaxWidth(array);
if (array != null) {
try {
int size = array.length();
for (int i = 0; i < size; ++i) {
JSONArray o = (JSONArray) array.get(i);
String key = o.getString(0);
String value = o.getString(1);
addItem(key, value);
}
} catch (Exception e) {
}
}
}
private void calculateLeftMaxWidth(JSONArray data) {
try {
int size = data.length();
for (int i = 0; i < size; ++i) {
JSONArray o = (JSONArray) data.get(i);
String key = o.getString(0);
String value = o.getString(1);
if (TextUtils.isEmpty(key) || TextUtils.isEmpty(value)) {
continue;
}
float curWidth = leftPaint.measureText(key);
if (curWidth > maxLeftWidth) {
maxLeftWidth = curWidth;
}
}
maxLeftWidth = maxLeftWidth + middlePadding;
} catch (Exception e) {
}
}
private void addItem(String key, String value) {
LinearLayout layout = getItemLayout();
TextView left = (TextView) layout.findViewById(R.id.left);
LinearLayout.LayoutParams params = new LinearLayout.LayoutParams(ViewGroup.LayoutParams.WRAP_CONTENT,
ViewGroup.LayoutParams.WRAP_CONTENT);
params.width = (int) maxLeftWidth;
left.setLayoutParams(params);
left.setText(key);
TextView right = (TextView) layout.findViewById(R.id.right);
right.setText(value);
root.addView(layout);
}
private LinearLayout getItemLayout() {
LinearLayout layout = (LinearLayout) LayoutInflater.from(this).inflate(R.layout.compose_item_layout, null);
return layout;
}
}
改計劃也須要先盤算右邊的最年夜占用寬度，來設置左邊占用的年夜小，每項的結構以下：
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="horizontal"
android:paddingTop="@dimen/text_padding_10"
tools:context=".activity.Typography1Activity">
<TextView
android:id="@+id/left"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginRight="@dimen/text_padding_10"
android:textColor="@color/color_black_999999"
android:textSize="@dimen/text_size_13"/>
<TextView
android:id="@+id/right"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_weight="1"
android:textColor="@color/black"
android:textSize="@dimen/text_size_13"/>
</LinearLayout>
每行有兩個TextView，右邊寬度為自順應，左邊占領剩下閣下的地位，在盤算出右邊最年夜寬度後，從新設置右邊每個TextView占用的寬度。
計劃6
方法與1差不多，然則不在繼續TextView，而是直接繼續View:
public class TypographyView4 extends View {
private Paint leftPaint = new Paint();
private Paint rightPaint = new Paint();
private int fullWidth;
private float textSize;
private JSONArray array;
private int middlePadding = 0;
float maxLeftWidth = 0;
int itemSize = 0;
public TypographyView4(Context context) {
super(context);
init();
}
public TypographyView4(Context context, AttributeSet attrs) {
super(context, attrs);
init();
}
public TypographyView4(Context context, AttributeSet attrs, int defStyleAttr) {
super(context, attrs, defStyleAttr);
init();
}
private void init() {
textSize = getResources().getDimensionPixelSize(R.dimen.text_size_13);
leftPaint.setAntiAlias(true);
leftPaint.setTextSize(textSize);
leftPaint.setColor(getResources().getColor(R.color.color_black_999999));
rightPaint.setAntiAlias(true);
rightPaint.setTextSize(textSize);
rightPaint.setColor(getResources().getColor(R.color.color_black));
middlePadding = getResources().getDimensionPixelSize(R.dimen.padding_value);
}
@Override
protected void onSizeChanged(int w, int h, int oldw, int oldh) {
super.onSizeChanged(w, h, oldw, oldh);
fullWidth = getWidth();// 全部textView的寬度
}
public void setText(JSONArray array) {
this.array = array;
if (array != null) {
try {
int size = itemSize = array.length();
for (int i = 0; i < size; ++i) {
JSONArray o = (JSONArray) array.get(i);
String key = o.getString(0);
String value = o.getString(1);
if (TextUtils.isEmpty(key) || TextUtils.isEmpty(value)) {
itemSize--;
continue;
}
float curWidth = leftPaint.measureText(key);
if (curWidth > maxLeftWidth) {
maxLeftWidth = curWidth;
}
}
maxLeftWidth = maxLeftWidth + middlePadding;
invalidate();
} catch (Exception e) {
}
}
}
@Override
protected void onDraw(Canvas canvas) {
if (array == null) {
return;
}
int lineCount = 0;
try {
JSONArray item;
float offsetY;
for (int i = 0; i < itemSize; ++i) {
item = (JSONArray) array.get(i);
offsetY = (lineCount + 1) * textSize;
canvas.drawText(item.getString(0), 0, offsetY, leftPaint);
String value = item.getString(1);
float valueWidth = rightPaint.measureText(value);
if (valueWidth > fullWidth - maxLeftWidth) {// 一行顯示不完
char[] textCharArray = value.toCharArray();
float charWidth;
float drawWidth = maxLeftWidth;
for (int j = 0; j < textCharArray.length; j++) {
charWidth = rightPaint.measureText(textCharArray, j, 1);
if (fullWidth - drawWidth < charWidth) {
lineCount++;
drawWidth = maxLeftWidth;
offsetY += textSize;
}
canvas.drawText(textCharArray, j, 1, drawWidth, offsetY, rightPaint);
drawWidth += charWidth;
}
} else {
canvas.drawText(value, maxLeftWidth, offsetY, rightPaint);
}
lineCount += 2;
}
} catch (JSONException e) {
e.printStackTrace();
}
}
}
該計劃重要繼續自View，不再繼續TextView，因為在在上述計劃中不在挪用super，是以TextView曾經退步為一個View,是以直接繼續View。
總結
由於右邊的寬度不肯定，是以一切的計劃都停止了異樣的一個操作，就是丈量了右邊顯示的最年夜寬度，後續的操作再依據該寬度停止調劑。上述的計劃中1，2，3，6都只需用一個View來停止顯示，4，5都須要多個View停止顯示。
完全的代碼可以在檢查鏈接長進行檢查。
以上就是本文的全體內容，願望對年夜家的進修有所贊助。
