Skip to content

Instantly share code, notes, and snippets.

@ViliusKraujutis
Created August 16, 2017 06:28
  • Star 0 You must be signed in to star a gist
  • Fork 0 You must be signed in to fork a gist
Star You must be signed in to star a gist
Save ViliusKraujutis/765b3eb5527bbc42886ba56c8f2dcf5f to your computer and use it in GitHub Desktop.
Use RxJava to detect changes
<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.ConstraintLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context="lt.andro.learnrxjava.MainActivity"
>
<TextView
android:id="@+id/main_output"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Hello World!"
app:layout_constraintLeft_toLeftOf="parent"
app:layout_constraintTop_toTopOf="parent"
/>
<EditText
android:id="@+id/main_input1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginLeft="16dp"
android:layout_marginRight="16dp"
android:layout_marginTop="16dp"
android:ems="10"
android:inputType="textPersonName"
app:layout_constraintLeft_toLeftOf="parent"
app:layout_constraintTop_toBottomOf="@id/main_output"
tools:text="Name"
/>
<EditText
android:id="@+id/main_input2"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginLeft="16dp"
android:layout_marginRight="16dp"
android:layout_marginTop="16dp"
android:ems="10"
android:inputType="textPersonName"
app:layout_constraintLeft_toLeftOf="parent"
app:layout_constraintTop_toBottomOf="@id/main_input1"
tools:text="Name"
/>
<EditText
android:id="@+id/main_input3"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginLeft="16dp"
android:layout_marginRight="16dp"
android:layout_marginTop="16dp"
android:ems="10"
android:inputType="textPersonName"
app:layout_constraintLeft_toLeftOf="parent"
app:layout_constraintTop_toBottomOf="@id/main_input2"
tools:text="Name"
/>
<EditText
android:id="@+id/main_input4"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginLeft="16dp"
android:layout_marginRight="16dp"
android:layout_marginTop="16dp"
android:ems="10"
android:inputType="textPersonName"
app:layout_constraintLeft_toLeftOf="parent"
app:layout_constraintTop_toBottomOf="@id/main_input3"
tools:text="Name"
/>
<RadioGroup
android:id="@+id/main_radio_group"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginLeft="16dp"
android:layout_marginRight="16dp"
android:layout_marginTop="16dp"
app:layout_constraintLeft_toLeftOf="parent"
app:layout_constraintTop_toBottomOf="@id/main_input4"
>
<RadioButton
android:id="@+id/main_radio1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Radio1"
/>
<RadioButton
android:id="@+id/main_radio2"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Radio2"
/>
<RadioButton
android:id="@+id/main_radio3"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Radio3"
/>
<RadioButton
android:id="@+id/main_radio4"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Radio4"
/>
</RadioGroup>
</android.support.constraint.ConstraintLayout>
apply plugin: 'com.android.application'
android {
compileSdkVersion 26
buildToolsVersion "26.0.1"
defaultConfig {
applicationId "lt.andro.learnrxjava"
minSdkVersion 15
targetSdkVersion 26
versionCode 1
versionName "1.0"
testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"
}
buildTypes {
release {
minifyEnabled false
proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
}
}
}
dependencies {
compile fileTree(dir: 'libs', include: ['*.jar'])
androidTestCompile('com.android.support.test.espresso:espresso-core:2.2.2', {
exclude group: 'com.android.support', module: 'support-annotations'
})
compile 'com.android.support:appcompat-v7:26.0.0-alpha1'
compile 'com.android.support.constraint:constraint-layout:1.0.2'
testCompile 'junit:junit:4.12'
compile 'io.reactivex.rxjava2:rxandroid:2.0.1'
compile 'io.reactivex.rxjava2:rxjava:2.1.2'
compile 'com.jakewharton.rxbinding2:rxbinding:2.0.0'
compile 'com.jakewharton.rxbinding2:rxbinding-support-v4:2.0.0'
compile 'com.jakewharton.rxbinding2:rxbinding-appcompat-v7:2.0.0'
compile 'com.jakewharton.rxbinding2:rxbinding-design:2.0.0'
compile 'com.jakewharton.rxbinding2:rxbinding-recyclerview-v7:2.0.0'
}
package lt.andro.learnrxjava;
import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.text.Editable;
import android.text.TextUtils;
import android.widget.RadioGroup;
import android.widget.TextView;
import com.jakewharton.rxbinding2.InitialValueObservable;
import com.jakewharton.rxbinding2.widget.RxRadioGroup;
import com.jakewharton.rxbinding2.widget.RxTextView;
import com.jakewharton.rxbinding2.widget.TextViewAfterTextChangeEvent;
import java.util.Arrays;
import java.util.List;
import io.reactivex.Flowable;
import io.reactivex.Observable;
import io.reactivex.annotations.NonNull;
import io.reactivex.functions.Consumer;
import io.reactivex.functions.Function;
import io.reactivex.functions.Function4;
public class MainActivity extends AppCompatActivity {
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
TextView outputView = (TextView) findViewById(R.id.main_output);
TextView input1View = (TextView) findViewById(R.id.main_input1);
TextView input2View = (TextView) findViewById(R.id.main_input2);
TextView input3View = (TextView) findViewById(R.id.main_input3);
TextView input4View = (TextView) findViewById(R.id.main_input4);
RadioGroup inputRG = (RadioGroup) findViewById(R.id.main_radio_group);
outputView.setText("output");
input1View.setText("input1");
input2View.setText("input2");
input3View.setText("input3");
input4View.setText("input4");
inputRG.check(R.id.main_radio2);
Consumer<? super CharSequence> output = RxTextView.text(outputView);
InitialValueObservable<TextViewAfterTextChangeEvent> rxInput1 = RxTextView.afterTextChangeEvents(input1View);
InitialValueObservable<TextViewAfterTextChangeEvent> rxInput2 = RxTextView.afterTextChangeEvents(input2View);
InitialValueObservable<TextViewAfterTextChangeEvent> rxInput3 = RxTextView.afterTextChangeEvents(input3View);
InitialValueObservable<TextViewAfterTextChangeEvent> rxInput4 = RxTextView.afterTextChangeEvents(input4View);
InitialValueObservable<Integer> rxInputRG = RxRadioGroup.checkedChanges(inputRG);
Observable<String> input1 = getInputAsStrings(rxInput1);
Observable<String> input2 = getInputAsStrings(rxInput2);
Observable<String> input3 = getInputAsStrings(rxInput3);
Observable<String> input4 = getInputAsStrings(rxInput4);
// combineV1(output, input1, input2, input3, input4);
combineV2(output, rxInputRG, input1, input2, input3, input4);
}
private void combineV2(Consumer<? super CharSequence> output, InitialValueObservable<Integer> rxInputRG, Observable<String> input1, Observable<String> input2, Observable<String> input3, Observable<String> input4) {
Function<Object[], Object> combiner = new Function<Object[], Object>() {
List<Object> initial;
@Override
public Object apply(@NonNull Object[] objects) throws Exception {
List<Object> combined = Arrays.asList(objects);
if (initial == null) {
initial = combined;
}
return initial.equals(combined);
}
};
Observable
.combineLatest(combiner, Flowable.bufferSize(), input1, input2, input3, input4, rxInputRG)
.map(new Function<Object, String>() {
@Override
public String apply(@NonNull Object o) throws Exception {
return o.toString();
}
})
.doOnNext(output)
.subscribe();
}
private void combineV1(Consumer<? super CharSequence> output, Observable<String> input1, Observable<String> input2, Observable<String> input3, Observable<String> input4) {
Function4<String, String, String, String, Boolean> checkForChanges = new Function4<String, String, String, String, Boolean>() {
String initialValue = "";
@Override
public Boolean apply(@NonNull String s1, @NonNull String s2, @NonNull String s3, @NonNull String s4) throws Exception {
String combined = s1 + ":" + s2 + ":" + s3 + ":" + s4;
if (TextUtils.isEmpty(initialValue)) initialValue = combined;
return initialValue.equals(combined);
}
};
Observable
.combineLatest(input1, input2, input3, input4, checkForChanges)
.map(new Function<Boolean, String>() {
@Override
public String apply(@NonNull Boolean aBoolean) throws Exception {
return aBoolean.toString();
}
})
.doOnNext(output)
.subscribe();
}
private Observable<String> getInputAsStrings(Observable<TextViewAfterTextChangeEvent> inputs) {
Function<TextViewAfterTextChangeEvent, String> toString = new Function<TextViewAfterTextChangeEvent, String>() {
@Override
public String apply(@NonNull TextViewAfterTextChangeEvent changeEvent) throws Exception {
Editable editable = changeEvent.editable();
if (editable != null) {
return editable.toString();
} else {
return "";
}
}
};
return inputs.map(toString);
}
}
Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment