Rxjava之RxTextView经典详解
2018-07-20 本文已影响490人
NoValue
大家都知道Rxjava神通广大,无所不能,并有效避免Call Hell(回调地狱)模式,使大量的监听事件clickListener变换成流式编程,提高代码阅读性,提升代码维护成本。今天我通过例子详解Rxjava中的RxTextview详解,让你一举搞懂Rxjava用法,语法以及操作实例(明白 简单掌握)。
实际用户场景举例
根据用户输入的价格(价格范围0.-1)、输入的数量(10-无限)计算出总预计收入,如果写错了(举例价格范围错误、数量不对)卖出按钮无效(disable).
如果用传统的edittext.setOnChangeListner要加两个,动态计算较为难以理解。用Rxjava 则合并两个动态计算的Observable,最后动态算出结果,代码如下。
Observable<CharSequence> priceObservable = RxTextView.textChanges(priceEdit.getEditText());
Observable<CharSequence> countObservable = RxTextView.textChanges(countEdit.getEditText());
sellBtnSubscription = Observable.combineLatest(priceObservable, countObservable,
(priceSequence, countSequence) -> {
if (priceSequence.toString().startsWith(".")) {
priceSequence = "0" + priceSequence;
priceEdit.setText("0.");
priceEdit.getEditText().setSelection(priceEdit.getText().length());
}
double inputPrice = StringUtils.isEmpty(priceSequence.toString()) ? 0 : Double.parseDouble(priceSequence.toString());
int inputCount = StringUtils.isEmpty(countSequence.toString()) ? 0 : Integer.parseInt(countSequence.toString());
return inputPrice > 0 && inputCount > 0;
}).subscribe(new Observer<Boolean>() {
@Override
public void onCompleted() {
}
@Override
public void onError(Throwable e) {
e.printStackTrace();
}
@Override
public void onNext(Boolean isSellBtnEnable) {
sellBtn.setEnabled(isSellBtnEnable);
String handFeetStr = "(含手续费)";
if (isSellBtnEnable) {
double predictedIncome = Double.parseDouble(priceEdit.getText().toString()) * Integer.parseInt(countEdit.getText());
predictedIncomeTv.setText(FormatUtil.formatMoney(predictedIncome) + "元"); //卖出联豆的预计收入(没有去除手续费的预估收入)
//( 含手续费 )
if (predictedIncome == 0) {
predictedIncomeTv.setText(FormatUtil.formatMoney(predictedIncome) + "元"); //卖出联豆的预计收入(没有去除手续费的预估收入)
} else {
predictedIncomeTv.setText(FormatUtil.formatMoney(predictedIncome) + "元" + handFeetStr); //卖出联豆的预计收入(没有去除手续费的预估收入)
}
} else {
predictedIncomeTv.setText(FormatUtil.formatMoney(0) + "元"); //卖出联豆的预计收入
}
}
});
}
简单详解:
获得两个EditText的 可被观察对象
获得两个edittext的可被观察的(observable<CharSequence>对象
Observable<CharSequence> priceObservable =
RxTextView.textChanges(priceEdit.getEditText());
Observable<CharSequence> countObservable =
RxTextView.textChanges(countEdit.getEditText());
综合运算
动态算出 价格、数量是否合理
sellBtnSubscription = Observable.combineLatest(priceObservable, countObservable,
(priceSequence, countSequence) -> {
if (priceSequence.toString().startsWith(".")) {
priceSequence = "0" + priceSequence;
priceEdit.setText("0.");
priceEdit.getEditText().setSelection(priceEdit.getText().length());
}
double inputPrice = StringUtils.isEmpty(priceSequence.toString()) ? 0 : Double.parseDouble(priceSequence.toString());
int inputCount = StringUtils.isEmpty(countSequence.toString()) ? 0 : Integer.parseInt(countSequence.toString());
return inputPrice > 0 && inputCount > 0;
}).subscribe(new Observer<Boolean>() {
@Override
public void onCompleted() {
}
@Override
public void onError(Throwable e) {
e.printStackTrace();
}
@Override
public void onNext(Boolean isSellBtnEnable) {
sellBtn.setEnabled(isSellBtnEnable);
String handFeetStr = "(含手续费)";
if (isSellBtnEnable) {
double predictedIncome = Double.parseDouble(priceEdit.getText().toString()) * Integer.parseInt(countEdit.getText());
predictedIncomeTv.setText(FormatUtil.formatMoney(predictedIncome) + "元"); //卖出XX币的预计收入(没有去除手续费的预估收入)
//( 含手续费 )
if (predictedIncome == 0) {
predictedIncomeTv.setText(FormatUtil.formatMoney(predictedIncome) + "元"); //卖出XX币的预计收入(没有去除手续费的预估收入)
} else {
predictedIncomeTv.setText(FormatUtil.formatMoney(predictedIncome) + "元" + handFeetStr); //卖出XX币的预计收入(没有去除手续费的预估收入)
}
} else {
predictedIncomeTv.setText(FormatUtil.formatMoney(0) + "元"); //卖出联豆的预计收入
}
}
});