Android開發完整項目案例-獲取驗證碼倒計時

需求：

登陸或者註冊時點擊獲取驗證碼按鈕，進行60s倒計時，倒計時過程中不允許點擊按鈕。倒計時秒數需要實時顯示

效果圖：

圖1是未獲取之前，圖2是點擊之後

思路：

倒計時一般有幾種解決方案，常用用Timer，Handler，RxJava。
不過經過測試Timer和Handler時間都有誤差，不準。項目建議採用RxJava

關鍵代碼：

在項目的build.gradle中添加RxJava2依賴

implementation 'io.reactivex.rxjava2:rxandroid:2.0.1'
  implementation 'io.reactivex.rxjava2:rxjava:2.0.7'  

注：如果項目已經有RxJava2就不用重複添加了

TimeUtils

public static Disposable dealCountDownS(long second, Consumer<Long> nextObserver, Consumer<Throwable> errorObserver, Action completeObserver ) {
    return Observable
            .interval(1, TimeUnit.SECONDS, AndroidSchedulers.mainThread())
            .take(second)
            .subscribe(nextObserver,errorObserver,completeObserver);
}  

開始使用：

public class RegOneNewActivity extends BaseActivity<RegOneIView, RegOnePresenter> implements RegOneIView {


@BindView(R.id.tv_get_code)
TextView tvGetCode;


//是否開啓倒計時
private boolean isStartCountDown;
private Disposable subscription;

@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    
     initHeadView(R.layout.activity_regist_one_new, false);
    
    showRealView();
}


@Override
protected void initPrClick() {
    super.initPrClick();
    
    //獲取驗證碼
    ViewShow.prClick(tvGetCode, new Action1() {
        @Override
        public void call(Object o) {
            if (!isStartCountDown) {
                onGetRegCode()
            }
        }
    });

   
}

    
public void onGetRegCode() {
    //獲取驗證碼成功，進行倒計時
    isStartCountDown = true;
    //Constant.CODE_COUNTDOWN_TIME :60
    tvGetCode.setText(Constant.CODE_COUNTDOWN_TIME + "s");
    
    subscription = TimeUtils.dealCountDownS(Constant.CODE_COUNTDOWN_TIME, new Consumer<Long>() {

        @Override
        public void accept(Long aLong) throws Exception {
            //每隔一秒
            if (null != tvGetCode) {
                tvGetCode.setText((TextUtils.concat(String.valueOf(Math.abs(aLong - Constant.CODE_COUNTDOWN_TIME)), "s")).toString());
            }
        }
    }, new Consumer<Throwable>() {
       //倒計時錯誤的回調
        @Override
        public void accept(Throwable throwable) throws Exception {
            if (null != tvGetCode) {
                
                tvGetCode.setText(mContext.getString(R.string.get_code));
            }
            isStartCountDown = false;
        }
    }, new Action() {
       //倒計時完成的回調
        @Override
        public void run() throws Exception {
            if (null != tvGetCode) {
                
                tvGetCode.setText(R.string.get_code);
            }
            isStartCountDown = false;
        }
    });


}


@Override
protected void onDestroy() {
    super.onDestroy();
    if (subscription != null && !subscription.isDisposed()) {
        subscription.dispose();
    }
}

}