在Android应用中，我有一个带有几个按钮的屏幕，TextView和ImageView。在执行期间拍摄的此屏幕的屏幕截图（“.jpg”文件）中，仅捕获TextView中的第一个和第二个文本行。有趣的是，最后一个屏幕截图包含TextView的所有行。
有人可以提出原因和适当的补救措施吗？
屏幕顶部有3个按钮（在拍摄屏幕之前不可见），然后TextView和ImageView位于底部。
---------------------布局文件（solveallline1.xml）------------------ ------
<RelativeLayout 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:paddingBottom="@dimen/activity_vertical_margin"
android:paddingLeft="@dimen/activity_horizontal_margin"
android:paddingRight="@dimen/activity_horizontal_margin"
android:paddingTop="@dimen/activity_vertical_margin"
tools:context=".SolveLine1" >
<LinearLayout
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical" >
<TableLayout
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:stretchColumns="*" >
<TableRow>
<Button
android:id="@+id/b_prev"
android:enabled="false"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Previous Step" />
<Button
android:id="@+id/b_next"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Next Step" />
<Button
android:id="@+id/b_exit"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Exit" />
</TableRow>
</TableLayout>
<TextView
android:id="@+id/DrawingTextView"
android:layout_width="match_parent"
android:layout_height="wrap_content"/>
<ImageView
android:id="@+id/DrawingImageView"
android:layout_width="wrap_content"
android:layout_height="wrap_content">
</ImageView>
</LinearLayout>
</RelativeLayout>
代码中有13个步骤。在每个步骤结束后，拍摄屏幕截图。每个屏幕截图中ImageView的高度根据前一个屏幕截图的TextView中的文本行数而变化。因此，如果与先前的屏幕截图相比，每个屏幕截图的TextView中的线条数量都会被截断。 （例如，步骤11的屏幕截图仅显示2个文本行，因为step10在TextView中有2个文本行）
-----------在步骤10＆amp ;;中调用屏幕截图功能的代码11：-----------
void drawStep10(){
p1=getPaint(p1,"white",getStokeWidth(pxl),getTextSize(pxl),false);
canvas.drawText("Step9", brx / 4, bry - pxl*2/100, p1);
p1=getPaint(p1,"black",getStokeWidth(pxl),getTextSize(pxl),false);
canvas.drawText("a'",aa_dash.x+pxl*3/100,aa_dash.y+pxl*5/100,p1);
canvas.drawText("b1'",b1_dash.x-pxl*7/100,b1_dash.y+pxl*5/100,p1);
aaa_dash.drawLn(canvas,p1,a,aa_dash);
b1b1_dash.drawLn(canvas,p1,b1,b1_dash);
p1=getPaint(p1,"blue",getStokeWidth(pxl),getTextSize(pxl),false);
canvas.drawText("Step10", brx / 4, bry - pxl*2/100, p1);
len4=b1_dash.x-aa_dash.x;
alfa = (float)Math.asin((d.y-q.y)/(float)len4);
dalfa = (float)Math.toDegrees(alfa);//alfa in degrees
len5 = len4*Math.cos(alfa);
ilen5 = Integer.valueOf(len5.intValue());
b2_dash = new Point(aa_dash.x+ilen5,q.y);
RectF oval = new RectF();
oval.set(aa_dash.x-len4,aa_dash.y-len4,aa_dash.x+len4,aa_dash.y+len4);
canvas.drawArc(oval,0,dalfa*(-1),false,p1);
canvas.drawText("b2'",b2_dash.x+pxl*3/100,b2_dash.y+pxl*5/100,p1);
p1=getPaint(p1,"red",getStokeWidth(pxl),getTextSize(pxl),false);
canvas.drawLine(aa_dash.x,aa_dash.y,b2_dash.x,b2_dash.y,p1);
canvas.drawText("<-- center", aa_dash.x+pxl*1/100, aa_dash.y+pxl*1/100, p1);
canvas.drawText("<-- radius", ((aa_dash.x+b2_dash.x)/2)+pxl*2/100,(aa_dash.y+b2_dash.y)/2, p1);
drawingTextView.setText("Draw an Arc b1'b2' with Point a' as center. The Arc b1'b2'" +
" intersects Line pq at Point b2'");
drawingImageView.invalidate();
takeScreenshot("Step10");
}
void drawStep11(){
p1=getPaint(p1,"white",getStokeWidth(pxl),getTextSize(pxl),false);
canvas.drawText("Step10", brx / 4, bry - pxl*2/100, p1);
canvas.drawLine(aa_dash.x,aa_dash.y,b2_dash.x,b2_dash.y,p1);
canvas.drawText("<-- center", aa_dash.x+pxl*1/100, aa_dash.y+pxl*1/100, p1);
canvas.drawText("<-- radius", ((aa_dash.x+b2_dash.x)/2)+pxl*2/100,(aa_dash.y+b2_dash.y)/2, p1);
p1=getPaint(p1,"black",getStokeWidth(pxl),getTextSize(pxl),false);
RectF oval = new RectF();
oval.set(aa_dash.x-len4,aa_dash.y-len4,aa_dash.x+len4,aa_dash.y+len4);
canvas.drawArc(oval,0,dalfa*(-1),false,p1);
canvas.drawText("b2'",b2_dash.x+pxl*3/100,b2_dash.y+pxl*5/100,p1);
p1=getPaint(p1,"blue",getStokeWidth(pxl),getTextSize(pxl),false);
canvas.drawText("Step11", brx / 4, bry - pxl*2/100, p1);
aa_dashb2_dash = new Line();
aa_dashb2_dash.drawLn(canvas,p1,aa_dash,b2_dash);
p1=getPaint(p1,"green",getStokeWidth(pxl),getTextSize(pxl),false);
canvas.drawText("<-- ϴ =" + theta, adx+pxl*4/100, ady , p1);
canvas.drawText("<-- Φ =" + phi, a.x+pxl*4/100, a.y+pxl*3/100 , p1);
canvas.drawText("<-- α =" + Math.floor(dalfa * 100) / 100, aa_dash.x+pxl*4/100, aa_dash.y , p1);
drawingTextView.setText("Draw a Line a'b2'. Measure Angle b1'a'b2'(α)= " +
Math.floor(dalfa * 100) / 100+"\n"+
"Note4:Line a'b2' is the projection of line and is the Front View of the line" +
" making an angle Φ = "+ phi+" with VP and ϴ = "+theta+" with HP. Angle α = " +
Math.floor(dalfa * 100) / 100+
" is made by the projection of the line with HP");
drawingImageView.invalidate();
takeScreenshot("Step11");
}
-----------------截图功能：-------------------------- -
private void takeScreenshot(String s1) {
try {
String mPath = Environment.getExternalStorageDirectory().toString() + "/" + s1 + ".jpg";
View v1 = getWindow().getDecorView().getRootView();
v1.setDrawingCacheEnabled(true);
Bitmap b1 = Bitmap.createBitmap(v1.getDrawingCache());
v1.setDrawingCacheEnabled(false);
imageFile = new File(mPath);
FileOutputStream outputStream = new FileOutputStream(imageFile);
int quality = 100;
b1.compress(Bitmap.CompressFormat.JPEG, quality, outputStream);
outputStream.flush();
outputStream.close();
}
catch (Throwable e) {
e.printStackTrace();
}
}