我想在一块文本旁边显示一条蓝色的线，就像这样：
这是我的代码：
<TextView
android:id="@+id/textView1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:drawableLeft="@drawable/blue_line" />
blue_line是一个jpg文件，里面有一个蓝色的矩形。它在TextView中显示时始终保持其原始大小。我该如何根据文本高度动态调整它的高度？比如当文本很少时使其变短，而当文本较多时使其变长....
您可以通过为图像设置边界来在代码中尝试实现此操作。
textView1.getViewTreeObserver()
.addOnGlobalLayoutListener(new OnGlobalLayoutListener() {
@Override
public void onGlobalLayout() {
Drawable img = ActivityName.this.getContext().getResources().getDrawable(
R.drawable.blue_line);
img.setBounds(0, 0, img.getIntrinsicWidth() * textView1.getMeasuredHeight() / img.getIntrinsicHeight(), textView1.getMeasuredHeight());
textView1.setCompoundDrawables(img, null, null, null);
textView1.getViewTreeObserver().removeOnGlobalLayoutListener(this);
}
});
<?xml version="1.0" encoding="utf-8"?>
<bitmap
xmlns:android="http://schemas.android.com/apk/res/android"
android:scaleType="fitXY"
android:src="@drawable/total_calories"/>
XML中的TextView：
<TextView
android:id="@+id/title_total_cal"
style="@style/title_stats_textview"
android:drawableLeft="@drawable/total_calories_drawable"/>
<RelativeLayout
android:layout_width="wrap_content"
android:layout_height="wrap_content" >
<ImageView
android:id="@+id/imageView"
android:layout_width="wrap_content"
android:layout_height="match_parent"
android:src="@drawable/btndr" />
<TextView
android:id="@+id/textView1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_toRightOf="@+id/imageView" />
</RelativeLayout>
不幸的是，setBounds 对我来说无法工作，所以我不得不使用一种变通方法。
// Turn wanted drawable to bitmap
Drawable dr = getResources().getDrawable(R.drawable.somedrawable);
Bitmap bitmap = ((BitmapDrawable) dr).getBitmap();
// I had a square image with same height and width so I needed only TextView height (getLineHeight)
int size = textView1.getLineHeight();
Drawable d = new BitmapDrawable(getResources(), Bitmap.createScaledBitmap(bitmap, size, size, true));
textView1.setCompoundDrawables(d, null, null, null);
// Now we can set some spacing between text and image
textView1.setCompoundDrawablePadding(10);
这不是性能最佳的解决方案，因为会创建新的位图，但仍然有效。
简单来说，将您的图像保留为9patch drawable。
您可以将android:drawableLeft="@drawable/checkmark"添加到您的textview中。您还可以设置drawablePadding以使textview整洁有序。
android:drawableLeft="@drawable/button_icon"
android:drawablePadding="2dip"
这是创建9patch可绘制对象的链接。
<TextView android:text="@string/txtUserName"
android:id="@+id/txtUserName"
android:layout_width="160dip"
android:layout_height="60dip"
android:layout_gravity="center"
android:drawableLeft="@drawable/button_icon"
android:drawablePadding="2dip"
/>
public class FullHeightLineDrawable extends Drawable {
private Paint mPaint;
private int mHeight;
public FullHeightLineDrawable(int height) {
mPaint = new Paint();
mPaint.setColor(CompatUtils.getColor(R.color.colorAccent));
mPaint.setAntiAlias(true);
mPaint.setStrokeWidth(15);
mHeight = height;
}
@Override
public void draw(Canvas canvas) {
canvas.drawLine(0, -mHeight, 0, mHeight, mPaint);
}
@Override
public void setAlpha(int alpha) {
}
@Override
public void setColorFilter(ColorFilter colorFilter) {
}
@Override
public int getOpacity() {
return 0;
}
}
使用方法：
final Drawable drawable = new FullHeightLineDrawable(getHeight());
mTextView.setTextColor(watchingColor);
mTextView.setCompoundDrawablesWithIntrinsicBounds(drawable, null, null, null);
TextView的类，并在onPreDrawListener中调整可绘制对象的大小。public class MyTextView extends AppCompatTextView {
public MyTextView(Context context, AttributeSet attrs, int style) {
super(context, attrs, style);
fitCompoundDrawableToLineHeight();
}
private void fitCompoundDrawableToLineHeight() {
OnPreDraw.run(this, () -> {
final Drawable[] cd = getCompoundDrawables();
Arrays.stream(cd)
.filter(drawable -> drawable != null)
.forEach(d -> d.setBounds(0, 0, getLineHeight(), getLineHeight()));
setCompoundDrawables(cd[0], cd[1], cd[2], cd[3]);
});
}
}
// Convenience class that abstracts onPreDraw logic
public class OnPreDraw {
public static void run(View view, Runnable task) {
view.getViewTreeObserver().addOnPreDrawListener(new ViewTreeObserver.OnPreDrawListener() {
@Override
public boolean onPreDraw() {
if (!view.getViewTreeObserver().isAlive()) {
return true;
}
view.getViewTreeObserver().removeOnPreDrawListener(this);
task.run();
return true;
}
});
}
}
我将这个方法抽象出来。当可绘制对象位于TextView的左侧并进行动态缩放时，它可以正常工作。如果可绘制对象位于右侧，则此方法无法正常工作，需要找出原因。但是您可以直接使用textView.setcompounddrawableswithintrinsicbounds()方法，并提供正确大小的Drawable资源。
@RequiresApi(api = Build.VERSION_CODES.HONEYCOMB)
public static void ajustCompoundDrawableSizeWithText(final TextView textView, final Drawable leftDrawable, final Drawable topDrawable, final Drawable rightDrawable, final Drawable bottomDrawable) {
textView.addOnLayoutChangeListener(new View.OnLayoutChangeListener() {
@Override
public void onLayoutChange(View v, int left, int top, int right, int bottom, int oldLeft, int oldTop, int oldRight, int oldBottom) {
if(leftDrawable != null){
leftDrawable.setBounds(0, 0, (int)textView.getTextSize(), (int)textView.getTextSize());
}
if(topDrawable != null){
topDrawable.setBounds(0, 0, (int)textView.getTextSize(), (int)textView.getTextSize());
}
if(rightDrawable != null){
rightDrawable.setBounds(0, 0, (int)textView.getTextSize(), (int)textView.getTextSize());
}
if(bottomDrawable != null){
bottomDrawable.setBounds(0, 0, (int)textView.getTextSize(), (int)textView.getTextSize());
}
textView.setCompoundDrawables(leftDrawable, topDrawable, rightDrawable, bottomDrawable);
textView.removeOnLayoutChangeListener(this);
}
});
}
您需要创建一个水平的XML布局，左侧有蓝色线条，右侧有TextView文本框。然后将该布局用作项，并创建一个包含这些项的ListView列表。类似于here，但更简单一些。