android的动态代码

1，Android代码设置Shape,corners,Gradient  （http://blog.csdn.net/houshunwei/article/details/17392409）

 

int strokeWidth = 5; // 3dp 边框宽度
    int roundRadius = 15; // 8dp 圆角半径
    int strokeColor = Color.parseColor("#2E3135");//边框颜色
    int fillColor = Color.parseColor("#DFDFE0");//内部填充颜色

    GradientDrawable gd = new GradientDrawable();//创建drawable
    gd.setColor(fillColor);
    gd.setCornerRadius(roundRadius);
    gd.setStroke(strokeWidth, strokeColor);

setBackgroundDrawable(gd);

但是如果想设置Gradient的渐变色该咋办呢？

方法是改变GradientDrawable的创建方法：

int colors[] = { 0xff255779 , 0xff3e7492, 0xffa6c0cd };//分别为开始颜色，中间夜色，结束颜色

GradientDrawable gd = new GradientDrawable(GradientDrawable.Orientation.TOP_BOTTOM, colors);

参考：

http://stackoverflow.com/questions/17667964/how-to-create-shape-with-solid-corner-stroke-in-java-code

http://stackoverflow.com/questions/4177401/gradientdrawable-in-code

http://www.iteye.com/topic/1117635


2，，checkbox 代码设计

//取得CheckBox对象

CheckBox checkBox = (CheckBox) findViewById(R.id.checkBox);

 

//取得设置好的drawable对象

Drawable drawable = this.getResources().getDrawable(R.drawable.checkbox_style);

 

//设置drawable对象的大小

drawable.setBounds(0,0,40,40);

 

//设置CheckBox对象的位置，对应为左、上、右、下

checkBox.setCompoundDrawables(drawable,null,null,null);

3， Android 动态创建Drawable selector

http://blog.csdn.net/csm_qz/article/details/48520925

创建selector有两种方法，一种是定义xml文件,一种是创建StateListDrawable对象，完全可以用创建StateListDrawable来代替xml，它的好处是可以在程序运行时动态的调整背景颜色或者背景图片。

一.xml创建selector方法如下： 
定义一个switch_selector.xml

<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android">
    <item android:drawable="@drawable/switch_bg_disabled_emui" android:state_enabled="false"/>
    <item android:drawable="@drawable/switch_bg_on_emui" android:state_pressed="true"/>
    <item android:drawable="@drawable/switch_bg_on_emui" android:state_focused="true"/>
    <item android:drawable="@drawable/switch_bg_on_emui" android:state_checked="true"/>
    <item android:drawable="@drawable/switch_bg_off_emui"/>
</selector>

在Activity按下面方法使用

Drawable drawable = getResourse().getDrawable(R.drawable.switch_selector);
ImageView iv = new ImageView(this);
iv.setBackground(drawable);

二.用StateListDrawable来代替xml创建selector:

        private StateListDrawable createDrawableSelector(Context context)
        {
            Drawable checked = context.getResources().getDrawable(R.drawable.switch_bg_on_emui);
            Drawable unchecked = context.getResources().getDrawable(R.drawable.switch_bg_off_emui);
            Drawable disabled = context.getResources().getDrawable(R.drawable.switch_bg_disabled_emui);
            StateListDrawable stateList = new StateListDrawable();
            int statePressed = android.R.attr.state_pressed;
            int stateChecked = android.R.attr.state_checked;
            int stateFocused = android.R.attr.state_focused;
            int stateensable = android.R.attr.state_enabled;
            stateList.addState(new int[] {-stateensable}, disabled);
            stateList.addState(new int[] {stateChecked}, checked);
            stateList.addState(new int[] {statePressed}, checked);
            stateList.addState(new int[] {stateFocused}, checked);
            stateList.addState(new int[] {}, unchecked);
            return stateList;
        }

其中stateList.addState（）表示一个状态对应一个Drawable,在Activity里面按下面方法使用

Drawable drawable = createDrawableSelector(this);
ImageView iv = new ImageView(this);
iv.setBackground(drawable);


4，动态获取R.drawable.xx资源

String imageName = "index_fragmen"+getColor();
final int resId = context.getResources().getIdentifier(imageName, "drawable", context.getPackageName());
if (resId != 0) {
    Log.e("mytest", "可以获取到");
    holder.btnCoupon.setBackgroundResource(resId);
}