在java代码中设置margin

我们平常可以直接在xml里设置margin，如：

<ImageView android:layout_margin="5dip" android:src="@drawable/image" />

但是有些情况下，需要在java代码里来写，可是View本身没有setMargin方法，怎么办呢？

通过查阅android api，我们发现android.view.ViewGroup.MarginLayoutParams有个方法setMargins(left, top, right, bottom).

其直接的子类有: FrameLayout.LayoutParams, LinearLayout.LayoutParams and RelativeLayout.LayoutParams.

使用方法:

LinearLayout.LayoutParams lp = new LinearLayout.LayoutParams(LinearLayout.LayoutParams.WRAP_CONTENT, LinearLayout.LayoutParams.WRAP_CONTENT);
lp.setMargins(10, 20, 30, 40);
imageView.setLayoutParams(lp);

 原文:http://greatverve.cnblogs.com/archive/2012/01/29/android-margin.html

android 使用代码实现 RelativeLayout布局

 RelativeLayout rl = new RelativeLayout(this);
        
        Button btn1 = new Button(this);
        btn1.setText("----------------------");
        btn1.setId(1);
        
        RelativeLayout.LayoutParams lp1 = new RelativeLayout.LayoutParams(ViewGroup.LayoutParams.WRAP_CONTENT, ViewGroup.LayoutParams.WRAP_CONTENT);
        lp1.addRule(RelativeLayout.ALIGN_PARENT_TOP);
        lp1.addRule(RelativeLayout.CENTER_HORIZONTAL, RelativeLayout.TRUE);
        // btn1 位于父 View 的顶部，在父 View 中水平居中
        rl.addView(btn1, lp1 );
       
        Button btn2 = new Button(this);
        btn2.setText("|
|
|
|
|
|");
        btn2.setId(2);
       
        RelativeLayout.LayoutParams lp2 = new RelativeLayout.LayoutParams(ViewGroup.LayoutParams.WRAP_CONTENT, ViewGroup.LayoutParams.WRAP_CONTENT);
        lp2.addRule(RelativeLayout.BELOW, 1);
        lp2.addRule(RelativeLayout.ALIGN_LEFT, 1);
        // btn2 位于 btn1 的下方、其左边和 btn1 的左边对齐
        rl.addView(btn2, lp2);
       
        Button btn3 = new Button(this);
        btn3.setText("|
|
|
|
|
|");
        btn3.setId(3);
       
        RelativeLayout.LayoutParams lp3 = new RelativeLayout.LayoutParams(ViewGroup.LayoutParams.WRAP_CONTENT, ViewGroup.LayoutParams.WRAP_CONTENT);
       lp3.addRule(RelativeLayout.BELOW, 1);
        lp3.addRule(RelativeLayout.RIGHT_OF, 2);
        lp3.addRule(RelativeLayout.ALIGN_RIGHT, 1);
        // btn3 位于 btn1 的下方、btn2 的右方且其右边和 btn1 的右边对齐（要扩充）
        rl.addView(btn3,lp3);
       
        Button btn4 = new Button(this);
        btn4.setText("--------------------------------------------");
        btn4.setId(4);
       
        RelativeLayout.LayoutParams lp4 = new RelativeLayout.LayoutParams(ViewGroup.LayoutParams.WRAP_CONTENT, ViewGroup.LayoutParams.WRAP_CONTENT);
        lp4.addRule(RelativeLayout.BELOW, 2);
        lp4.addRule(RelativeLayout.CENTER_HORIZONTAL, RelativeLayout.TRUE);
        // btn4 位于 btn2 的下方，在父 Veiw 中水平居中
        rl.addView(btn4,lp4);
       
       
        setContentView(rl);

原文：http://kukuqiu.iteye.com/blog/1018396

动态修改RelativeLayout的宽高：

参数可以.属性设置，但数值是像素，需要转化为dp单位。

RelativeLayout.LayoutParams linearParams =  (RelativeLayout.LayoutParams)rela_addnote_notetype.getLayoutParams();  
        linearParams.height = 44;  
        rela_addnote_notetype.setLayoutParams(linearParams);  

原文：http://blog.csdn.net/chenguang79/article/details/37874793

 Android适配所需知识点LayoutParams：

http://www.android100.org/html/201406/05/18971.html