添加 Android/Demo1/TextViewAutoLayout.java

Android/Demo1/TextViewAutoLayout.java

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+
+import android.content.Context;
+import android.text.Layout;
+import android.text.StaticLayout;
+import android.text.TextPaint;
+import android.util.AttributeSet;
+import android.view.View;
+import android.view.ViewGroup;
+import android.widget.TextView;
+
+/**
+ * TextView + View 动态布局
+ * 该布局目前仅支持TextView + View 组合。
+ * 来源:https://www.loongwind.com/archives/217.html
+ */
+public class CustomLayout extends ViewGroup {
+    //单行显示
+    private static final int SINGLE_LINE = 0x01;
+    //多行显示
+    private static final int MULTI_LINE = 0x02;
+    //显示到下一行
+    private static final int NEXT_LINE = 0x03;
+    //显示样式
+    private int type;
+    //绘制文字最后一行的顶部坐标
+    private int lastLineTop;
+    //绘制文字最后一行的右边坐标
+    private float lastLineRight;
+
+    public CustomLayout(Context context) {
+        super(context);
+    }
+
+    public CustomLayout(Context context, AttributeSet attrs) {
+        super(context, attrs);
+    }
+
+    public CustomLayout(Context context, AttributeSet attrs, int defStyleAttr) {
+        super(context, attrs, defStyleAttr);
+    }
+
+
+    protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
+        int childCount = getChildCount();
+        int w = MeasureSpec.getSize(widthMeasureSpec);
+        if (childCount == 2) {
+            TextView tv = null;
+            if(getChildAt(0) instanceof  TextView){
+                tv = (TextView) getChildAt(0);
+                initTextParams(tv.getText(), tv.getMeasuredWidth(), tv.getPaint());
+            }else{
+                throw new RuntimeException("CustomLayout first child view not a TextView");
+            }
+
+            View sencodView = getChildAt(1);
+
+            //测量子view的宽高
+            measureChildren(widthMeasureSpec, heightMeasureSpec);
+
+            //两个子view宽度相加小于该控件宽度的时候
+            if (tv.getMeasuredWidth() + sencodView.getMeasuredWidth() <= w) {
+                int width = tv.getMeasuredWidth()+sencodView.getMeasuredWidth();
+                //计算高度
+                int height = Math.max(tv.getMeasuredHeight(), sencodView.getMeasuredHeight());
+                //设置该viewgroup的宽高
+                setMeasuredDimension(width, height);
+                type = SINGLE_LINE;
+                return;
+            }
+            if (getChildAt(0) instanceof TextView) {
+                //最后一行文字的宽度加上第二个view的宽度大于viewgroup宽度时第二个控件换行显示
+                if (lastLineRight + sencodView.getMeasuredWidth() > w) {
+                    setMeasuredDimension(tv.getMeasuredWidth(), tv.getMeasuredHeight() + sencodView.getMeasuredHeight());
+                    type = NEXT_LINE;
+                    return;
+                }
+
+                int height = Math.max(tv.getMeasuredHeight(), lastLineTop + sencodView.getMeasuredHeight());
+                setMeasuredDimension(tv.getMeasuredWidth(), height);
+                type = MULTI_LINE;
+            }
+        } else {
+            throw new RuntimeException("CustomLayout child count must is 2");
+        }
+
+    }
+
+
+    protected void onLayout(boolean changed, int l, int t, int r, int b) {
+        if (type == SINGLE_LINE || type == MULTI_LINE) {
+            TextView tv = (TextView) getChildAt(0);
+            View v1 = getChildAt(1);
+            //设置第二个view在Textview文字末尾位置
+            tv.layout(0, 0, tv.getMeasuredWidth(), tv.getMeasuredHeight());
+            int left = (int) lastLineRight;
+            int top  = lastLineTop;
+            //最后一行的高度 注:通过staticLayout得到的行高不准确故采用这种方式
+            int lastLineHeight = tv.getBottom()-tv.getPaddingBottom() -lastLineTop;
+            //当第二view高度小于单行文字高度时竖直居中显示
+            if(v1.getMeasuredHeight() < lastLineHeight){
+                top = lastLineTop + (lastLineHeight - v1.getMeasuredHeight())/2;
+            }
+            v1.layout(left, top, left + v1.getMeasuredWidth(), top+v1.getMeasuredHeight());
+        } else if (type == NEXT_LINE) {
+            View v0 = getChildAt(0);
+            View v1 = getChildAt(1);
+            //设置第二个view换行显示
+            v0.layout(0, 0, v0.getMeasuredWidth(), v0.getMeasuredHeight());
+            v1.layout(0, v0.getMeasuredHeight(), v1.getMeasuredWidth(), v0.getMeasuredHeight() + v1.getMeasuredHeight());
+        }
+    }
+
+    /**
+     * 得到Textview绘制文字的基本信息
+     * @param text Textview的文字内容
+     * @param maxWidth Textview的宽度
+     * @param paint 绘制文字的paint
+     */
+    private void initTextParams(CharSequence text, int maxWidth, TextPaint paint) {
+        StaticLayout staticLayout = new StaticLayout(text, paint, maxWidth, Layout.Alignment.ALIGN_NORMAL, 1.0f, 0.0f, false);
+        int lineCount = staticLayout.getLineCount();
+        lastLineTop = staticLayout.getLineTop(lineCount - 1);
+        lastLineRight = staticLayout.getLineRight(lineCount - 1);
+    }
+
+}