Since Android, mobile technology has become a big part of people’s lives for different reasons, and it is now main focus of Android app developers. In fact, out of those different reasons, the success of Android is the ability to interact using different accessibility features and Android gestures.
As a matter of fact, app developers of today have set new limits to the term User Interactions.
In today’s Android app tutorial, we’ll see the implementation process of Android gestures to help you build Android app.
Let’s Get Started
Create a new project in Android Studio.
Select your target device.
In the next tab, add an activity to mobile -> Select Empty Activity.
Lastly, customize the activity.
Start Code Integration
Activity.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:id="@+id/activity_main"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
android:paddingBottom="@dimen/activity_vertical_margin"
android:paddingLeft="@dimen/activity_horizontal_margin"
android:paddingRight="@dimen/activity_horizontal_margin"
android:paddingTop="@dimen/activity_vertical_margin">
<Button
android:text="Add Image to Gesture area"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:id="@+id/btn1" />
<TextView
android:text="Drag with finger,\n2 finger pinch for scale\n3 fingers to rotate\nDouble tap to delete image"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:id="@+id/textView" />
<RelativeLayout
android:id="@+id/rootLayout"
android:layout_width="match_parent"
android:layout_height="match_parent">
</RelativeLayout>
</LinearLayout>
6.MainActivity.java
package com.spaceo.gesturesdemo;
import android.content.DialogInterface;
import android.support.v7.app.AlertDialog;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.util.Log;
import android.view.MotionEvent;
import android.view.ScaleGestureDetector;
import android.view.View;
import android.view.ViewGroup;
import android.widget.Button;
import android.widget.ImageView;
import android.widget.LinearLayout;
import android.widget.RelativeLayout;
import android.widget.Toast;
public class MainActivity extends AppCompatActivity implements View.OnTouchListener{
ViewGroup editingLayout =null;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
editingLayout = (ViewGroup) findViewById(R.id.rootLayout);
Button NewImage = (Button)findViewById(R.id.btn1);
NewImage.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
addNewImage();
}
});
clickCount = 0;
}
private void addNewImage() {
final ImageView iv = new ImageView(this);
iv.setImageResource(R.mipmap.ic_launcher);
LinearLayout.LayoutParams layoutParams = new LinearLayout.LayoutParams(150, 150);
iv.setLayoutParams(layoutParams);
editingLayout.addView(iv, layoutParams);
iv.setOnTouchListener(this);
}
int clickCount;
private int posX;
private int posY;
long startTime = 0 ;
public boolean onTouch(final View view, MotionEvent event) {
final int X = (int) event.getRawX();
final int Y = (int) event.getRawY();
int pointerCount = event.getPointerCount();
switch (event.getAction() & MotionEvent.ACTION_MASK) {
case MotionEvent.ACTION_DOWN:
RelativeLayout.LayoutParams layoutParams = (RelativeLayout.LayoutParams) view.getLayoutParams();
posX = X - layoutParams.leftMargin;
posY = Y - layoutParams.topMargin;
break;
case MotionEvent.ACTION_UP:
if (startTime == 0){
startTime = System.currentTimeMillis();
}else {
if (System.currentTimeMillis() - startTime < 200) {
AlertDialog.Builder builder = new AlertDialog.Builder(MainActivity.this);
builder.setMessage("Are you sure you want to delete this?");
builder.setPositiveButton("Yes", new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialog, int which) {
view.setVisibility(View.GONE);
}
});
builder.setNegativeButton("No", new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialog, int which) {
dialog.dismiss();
}
});
AlertDialog alertDialog = builder.create();
alertDialog.show();
}
startTime = System.currentTimeMillis();
}
break;
case MotionEvent.ACTION_POINTER_DOWN:
break;
case MotionEvent.ACTION_POINTER_UP:
break;
case MotionEvent.ACTION_MOVE:
if (pointerCount == 1){
RelativeLayout.LayoutParams Params = (RelativeLayout.LayoutParams) view.getLayoutParams();
Params.leftMargin = X - posX;
Params.topMargin = Y - posY;
Params.rightMargin = -500;
Params.bottomMargin = -500;
view.setLayoutParams(Params);
}
if (pointerCount == 2){
Log.e("TAG","2 finger touched");
RelativeLayout.LayoutParams layoutParams1 = (RelativeLayout.LayoutParams) view.getLayoutParams();
layoutParams1.width = posX +(int)event.getX();
layoutParams1.height = posY + (int)event.getY();
view.setLayoutParams(layoutParams1);
}
//Rotation
if (pointerCount == 3){
//Rotate the ImageView
view.setRotation(view.getRotation() + 10.0f);
}
break;
}
// Schedules a repaint for the root Layout.
editingLayout.invalidate();
return true;
}
}And done!
Android gestures helps developers to build fluent and articulate Android apps. However, things can go wrong if you’re not a technical person. And, if that’s the case, or if you want your Android app idea to be developed into an app, write down your app features, build an MVP model first or hire Android app developer to implement all functionalities correctly.
Get a free copy of in-app customized gestures from Github.
You may also like,
- The Importance of In-app Mobile Gestures and How It Boosts App User Experience
- Create a Simple Android Gestures Detection App in Less Than 30 Minutes!
This page was last edited on April 21st, 2020, at 6:48.
