编写clearedit的安卓控件

1.写一个自定义的控件

public class ClearEditText extends AppCompatEditText implements
        View.OnFocusChangeListener, TextWatcher {

    public Drawable mClearDrawable;
    private boolean hasFocus;

    private static final String TAG = "ClearEditText";
    
    public ClearEditText(Context context, AttributeSet attrs) {
        super(context, attrs);

        init();
    }
    public void init(){
        //右侧清除按钮的图片资源
        mClearDrawable = getCompoundDrawables()[2];

        if(mClearDrawable==null){
            mClearDrawable = getResources().getDrawable(R.drawable.i_delete);
        }

        mClearDrawable.setBounds(0,0,mClearDrawable.getIntrinsicWidth(), mClearDrawable.getIntrinsicHeight());

        //设置清除按钮隐藏
        setClearIconVisble(false);
        //设置焦点改变的监听
        setOnFocusChangeListener(this);
        //设置输入框里面内容发生改变的监听
        addTextChangedListener(this);
    }
    //设置焦点改变的监听


    @Override
    public boolean onTouchEvent(MotionEvent event) {

        if(event.getAction()== MotionEvent.ACTION_UP){
            if(getCompoundDrawables()[2]!=null){
                Boolean touchable = event.getX()>(getWidth()-getTotalPaddingRight()) && (event.getX() < ((getWidth() - getPaddingRight())));
                if(touchable){
                    this.setText("");
                }
            }
        }
        return super.onTouchEvent(event);
    }



    /*
    *  设置清除按钮的样式
    * */
    private void setClearIconVisble(Boolean visible){
        Drawable right =visible ?mClearDrawable :null;
        setCompoundDrawables(getCompoundDrawables()[0],getCompoundDrawables()[1],right,getCompoundDrawables()[3]);
    }

    /*
    * 判断是否显示清除标签的方法
    * */
    private void showClearIcon(){
   
        if(hasFocus && getText().length()>0){

            setClearIconVisble(true);
        }else{
            setClearIconVisble(false);
        }
    }


    @Override
    public void onFocusChange(View view, boolean b) {

        hasFocus=b;
        showClearIcon();
    }

    @Override
    public void beforeTextChanged(CharSequence charSequence, int i, int i1, int i2) {

    }

    @Override
    public void onTextChanged(CharSequence charSequence, int i, int i1, int i2) {
        showClearIcon();
    }

    @Override
    public void afterTextChanged(Editable editable) {

    }
}

2.在布局文件中使用它

 <com.lingdangmao.demo_zidingyi_textview.ClearEditText
        android:id="@+id/clearedit"
        android:background="@drawable/rounded_edittext"
        android:drawablePadding="8dp"
        android:singleLine="true"
        android:drawableLeft="@drawable/search"
        android:drawableRight="@drawable/i_delete"
        android:hint="请输入要搜索的商品"
        android:imeOptions="actionSearch"
        android:layout_width="match_parent"
        android:layout_height="45dp" />

3.在activity里面写点击回车的执行逻辑

public class MainActivity extends AppCompatActivity implements View.OnKeyListener {

    private ClearEditText clearEditText;
    private String txt;
    private static final String TAG = "MainActivity";
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        clearEditText =findViewById(R.id.clearedit);
        clearEditText.setOnKeyListener(this);
    }

    @Override
    public boolean onKey(View view, int i, KeyEvent keyEvent) {
        //这里要做下keyEvent.getAction()==KeyEvent.ACTION_UP，防止执行2次一样的操作
        if(i==keyEvent.KEYCODE_ENTER && keyEvent.getAction()==KeyEvent.ACTION_UP){
            txt=clearEditText.getText().toString().trim();
            if(!TextUtils.isEmpty(txt)){
                //点击后的具体逻辑写在这里
                Log.d(TAG, "onKey: "+txt);
            }
        }
        return false;
    }
}

4.完成

有个问题，不知道为什么不能设置drawright的图片，只能用默认的删除图片