android——获取view的宽高
-
在activity生命周期方法:onCreate(),onStart(),onResume()中调用View.getWidth()和View.getHeight()方法获取View的高度是不可行的，因为此时布局没有加载是不可见状态。
还有当view的可见状态为：GONE，时获取的宽高也是0；
2. 解决办法：
（1）直接测量：
private void first() {
int width = View.MeasureSpec.makeMeasureSpec(0,
View.MeasureSpec.UNSPECIFIED);
int height = View.MeasureSpec.makeMeasureSpec(0,
View.MeasureSpec.UNSPECIFIED);
textView.measure(width, height);
int height1 = textView.getMeasuredHeight();
int width3 = textView.getMeasuredWidth();
System.out.println("first: 宽： " + width3 + " 高： " + height1);
}
（2）添加绘制view之前的监听
private void second() {
ViewTreeObserver vto = textView.getViewTreeObserver();
vto.addOnPreDrawListener(new
ViewTreeObserver.OnPreDrawListener() {
public boolean onPreDraw() {
int height = textView.getMeasuredHeight();
int width = textView.getMeasuredWidth();
System.out.println("second: 宽：" + width + " 高： " + height);
return true;
}
});
}
（3）添加整体布局监听
private void third() {
ViewTreeObserver vto = textView.getViewTreeObserver();
vto.addOnGlobalLayoutListener(new OnGlobalLayoutListener() {
public void onGlobalLayout() {
textView.getViewTreeObserver().removeGlobalOnLayoutListener(
this);
int height = textView.getMeasuredHeight();
int width = textView.getMeasuredWidth();
System.out.println("third: 宽：" + width + " 高： " + height);
}
});
}