[安卓]发送短信获取验证码倒计时

先看效果

GIF.gif

基于handler实现, 比timertask更省内存.

/**
 * Created by jin on 2017/4/17.
 * 倒计时按钮, 发短信
 */
public class CountdownButton extends Button{
    private GradientDrawable shapeBg;//shape背景
    private int mDisablecolor;//不可点击时背景颜色
    private int mNormalcolor;//正常的背景颜色.
    private int DEFAULT_TIME = 60;//倒计时时间

    public CountdownButton(Context context) {
        this(context, null);
    }

    public CountdownButton(Context context, AttributeSet attrs) {
        this(context, attrs, R.attr.buttonStyle);
    }

    public CountdownButton(Context context, AttributeSet attrs, int defStyleAttr) {
        super(context, attrs, defStyleAttr);
        init(context, attrs);
    }

    private String beforeText = "获取验证码";
    private void init(Context context, AttributeSet attrs) {
        TypedArray a = context.obtainStyledAttributes(attrs, R.styleable.CountDownTimerButton);
        // 默认背景
        mNormalcolor = a.getColor(R.styleable.CountDownTimerButton_normalcolor, 0xffff0000);
        // 不可点击时的背景
        mDisablecolor = a.getColor(R.styleable.CountDownTimerButton_disablecolor, 0xff00ff00);
        float dimension = a.getDimension(R.styleable.CountDownTimerButton_corner, UiUtils.dip2px(context, 8));
        a.recycle();

        shapeBg = new GradientDrawable();
        shapeBg.setColor(mNormalcolor);
        shapeBg.setCornerRadius(dimension);

        if (!TextUtils.isEmpty(this.getText().toString().trim())) {
            this.beforeText = this.getText().toString().trim();
        }
        this.setBackground(shapeBg);
        this.setText(beforeText);
    }

    public void startCountdown() {
        mHandler.sendEmptyMessageDelayed(0, 1000);
        shapeBg.setColor(mDisablecolor);
        this.setBackground(shapeBg);
        this.setClickable(false);
    }

    private Handler mHandler = new Handler(){
        @Override
        public void handleMessage(Message msg) {
            super.handleMessage(msg);
            switch (msg.what) {
                case 0:
                    if (DEFAULT_TIME >= 0) {
                        CountdownButton.this.setText(String.format("重新发送(%d)", DEFAULT_TIME--));
                        mHandler.sendEmptyMessageDelayed(0, 1000);
                    } else {
                        CountdownButton.this.setClickable(true);
                        shapeBg.setColor(mNormalcolor);
                        CountdownButton.this.setBackground(shapeBg);
                        CountdownButton.this.setText(beforeText);
                        DEFAULT_TIME = 60;
                        mHandler.removeCallbacksAndMessages(null);
                    }
                    break;
            }
        }
    };

    @Override
    protected void onDetachedFromWindow() {
        super.onDetachedFromWindow();
        mHandler.removeCallbacksAndMessages(null);
    }
}

values/attrs中

    <declare-styleable name="CountDownTimerButton">
        <attr name="normalcolor" format="color" />
        <attr name="disablecolor" format="color" />
        <attr name="corner" format="dimension"/>
    </declare-styleable>

使用方法

xml中:
和普通button一样定义,只是多了三个属性

  app:normalcolor="@color/themeOrange"
  app:disablecolor="@color/gray"
  app:corner="8dp"

分别是正常状态颜色/点击后的颜色/圆角大小
代码中:
在适当的时机调用startCountdown()方法即可.

by the way
xml中按钮可添加style="?android:attr/borderlessButtonStyle"这个属性屏蔽点击阴影