动态设置view的大小及其位置 【Android动态设置view的大小及其位置】需求就不说了，下面贴代码：
MainActivity
主要就是对view的操作，例如：
public class MainActivity extends Activity implements OnClickListener {private Button btn;
private ImageView iv;
private LinearLayout ll_group;
public boolean isFullScreen = true;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
initView();
}private void initView() {
btn = (Button) findViewById(R.id.btn);
iv = (ImageView) findViewById(R.id.iv);
ll_group = (LinearLayout) findViewById(R.id.ll_group);
btn.setOnClickListener(this);
}@Override
public void onClick(View v) {if (isFullScreen) { // 全屏转半屏
setViewSize(iv);
isFullScreen = false;
} else {
isFullScreen = true;
setViewFullScreen(iv);
}}/**
* 设置view的大小
*
* @param iv2
*/
private void setViewFullScreen(ImageView view) {
MarginLayoutParams margin = new MarginLayoutParams(view.getLayoutParams());
LinearLayout.LayoutParams layoutParams = new LinearLayout.LayoutParams(margin);
layoutParams.width = 1000 ;
layoutParams.height = 800 ;
view.setLayoutParams(layoutParams);
}/**
* 自定义设置位置及其大小
*
* @param iv2
*/
private void setViewSize(ImageView view) {
MarginLayoutParams margin = new MarginLayoutParams(view.getLayoutParams());
int dpTop = dp2px( 10);
int dpRight = dp2px( 10);
int dpLeft=dp2px( 10);
margin.setMargins(dpLeft, dpTop, dpRight, 0);
DisplayMetrics metric = new DisplayMetrics();
getWindowManager().getDefaultDisplay().getMetrics(metric);
LinearLayout.LayoutParams layoutParams = new LinearLayout.LayoutParams(margin);
layoutParams.width = 500;
layoutParams.height= 400;
view.setLayoutParams(layoutParams);
}
publicint dp2px(float dpValue){
final float scale=MainActivity.this.getResources().getDisplayMetrics().density;
return (int)(dpValue*scale+0.5f);
}
}xml
注意事项
动态变化的view设置宽高属性时，指向的引用类型，应该是该view的父控件。否则将会报：
java.lang.ClassCastException: android.widget.FrameLayout$LayoutParams
cannot be cast to android.widget.LinearLayout$LayoutParamsMarginLayoutParams margin = new MarginLayoutParams(view.getLayoutParams());
/**
*在xml中，view的父控件是LinearLayout这里要LinearLayout.LayoutParams.
*/
LinearLayout.LayoutParams layoutParams = new LinearLayout.LayoutParams(margin);
layoutParams.width = 1000 ;
layoutParams.height = 800 ;
view.setLayoutParams(layoutParams);
