Develop Reference

How to change the base color of an application

When I launch my application, the screen goes white before displaying my Splash Screen
I would like to remove if possible or put the background the same color as my Splash Screen
But I do not know how, Can someone help me
Thank you

You need to remove your splash screen code as the white screen is itself a splash, provided by android. You just need to change it according to your need.
You first need to create a drawable with name splash_screen.xml and put this code
<?xml version="1.0" encoding="utf-8"?>
<layer-list xmlns:android="http://schemas.android.com/apk/res/android">
<item
android:drawable="#color/black"/>
<item
android:drawable="#mipmap/ic_launcher_round"
android:gravity="center"/>
</layer-list>
after that you need to create a activity which launches your MainActivity
Something like this
class OnBoardingActivity : AppCompatActivity() {
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
DashboardActivity.launch(this)
finish()
}
}
then you need to overwrite the default splash screen with your styles.xml
<style name="SplashTheme" parent="Theme.AppCompat.NoActionBar">
<item name="android:windowBackground">#drawable/splash_screen</item>
</style>
after that last step is to add this theme in your manifest.
the activity which launches the app will have this style
<activity
android:name=".ui.onboarding.OnBoardingActivity"
android:label="#string/app_name"
android:screenOrientation="portrait"
android:theme="#style/SplashTheme">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>

you could use separate activity for your splash screen
xml
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="#dddddd"
tools:context=".SplashScreen">
<ImageView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_centerInParent="true"
android:src="#drawable/ic_icon" />
<TextView
android:id="#+id/text"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentBottom="true"
android:layout_centerHorizontal="true"
android:layout_marginBottom="20dp"
android:text="Splash Screen"
android:textSize="25sp" />
Class
public class SplashScreen extends AppCompatActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_splash_screen);
new Handler().postDelayed(new Runnable(){
#Override
public void run() {
Intent mainIntent = new Intent(getApplicationContext(),MainActivity.class);
SplashScreen.this.startActivity(mainIntent);
SplashScreen.this.finish();
}
}, 2000);
}
}
Manifest
( Launch Activity as SplashActivity )
<application
android:allowBackup="true"
android:icon="#mipmap/ic_launcher"
android:label="#string/app_name"
android:roundIcon="#mipmap/ic_launcher_round"
android:supportsRtl="true"
android:theme="#style/Theme.SplashtoMain">
<activity android:name=".MainActivity"/>
<activity android:name=".SplashScreen">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
</application>

How can I view "Hello World!" TextView in Android Studio?

I have just started learning development on Android, and I am not able to view "Hellow World!" TextView in the Design Tab.
MainActivity.java:
package com.dummy.demoapp;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
public class MainActivity extends AppCompatActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
}
}
activity_main.xml:
<?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=".MainActivity">
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Hello World!"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintLeft_toLeftOf="parent"
app:layout_constraintRight_toRightOf="parent"
app:layout_constraintTop_toTopOf="parent" />
</android.support.constraint.ConstraintLayout>
AndroidManifest.xml:
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.dummy.demoapp">
<application
android:allowBackup="true"
android:icon="#mipmap/ic_launcher"
android:label="#string/app_name"
android:roundIcon="#mipmap/ic_launcher_round"
android:supportsRtl="true"
android:theme="#style/AppTheme">
<activity android:name=".MainActivity">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
</application>
</manifest>
The TextView appears in the Component Tree, but the preview of the activity is totally blank:
I tried zooming in, but the TextView is just not there.
[EDIT]: The red exclamation (!) gives me the following message:
And refreshing doesn't solve the problem. Any help?

Go to style.xml and change this:
<style name="AppTheme" parent="Theme.AppCompat.Light.DarkActionBar">
to
<style name="AppTheme" parent="Base.Theme.AppCompat.Light.DarkActionBar">

Android Studio sometimes does not appear upto you've success build,
Build->Build&Run, then select your virtual device if there is a helloworld it's okay, it's not your code problem it's related with IDE.

I think it's you default AppTheme with color white , try to add color to TextView
android:textColor="#android:color/black"

Click on the blue icon at the top left corner and then click on force layout. and You will see the Hello World!

I am not getting splash screen in my app, only blank white screen is coming after that second activity is running

package cppandi.apjquotes;
import android.os.Bundle;
import android.app.Activity;
import android.content.Intent;
import android.os.Handler;
public class MainSplashScreen extends Activity {
/** Duration of wait **/
private final int SPLASH_DISPLAY_LENGTH = 5000;
/** Called when the activity is first created. */
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.front);
/* New Handler to start the Menu-Activity
* and close this Splash-Screen after some seconds.*/
new Handler().postDelayed(new Runnable(){
#Override
public void run() {
/* Create an Intent that will start the Menu-Activity. */
Intent mainIntent = new Intent(MainSplashScreen.this,MainActivity.class);
MainSplashScreen.this.startActivity(mainIntent);
MainSplashScreen.this.finish();
}
}, SPLASH_DISPLAY_LENGTH);
}
}
Here is my front.xml
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:orientation="vertical" android:layout_width="match_parent"
android:layout_height="match_parent">
<ImageView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
app:srcCompat="#mipmap/front"
android:id="#+id/imageView"
android:layout_alignParentLeft="true"
android:layout_alignParentStart="true" />
</RelativeLayout>
Here is my Manifest.xml
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="cppandi.apjquotes">
<application
android:allowBackup="true"
android:icon="#mipmap/ic_launcher"
android:label="#string/app_name"
android:supportsRtl="true"
android:theme="#style/AppTheme">
<activity
android:name=".MainSplashScreen"
android:label="#string/app_name">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<activity android:name=".MainActivity"
android:label="#string/app_name">
</activity>
<activity android:name=".quotes"
android:label="#string/app_name">
</activity>
<activity android:name=".about"
android:label="#string/app_name">
</activity>
</application>
After opened my android app it is showing like white screen for 5 seconds and it is going to next activity "Mainactivity", But my image in front.xml is not displaying.

try this:
<ImageView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:src="#mipmap/front" //change this
android:id="#+id/imageView"
android:layout_alignParentLeft="true"
android:layout_alignParentStart="true" />
srcCompat attribute is actually defined within AppCompat library.
From documentation:
app:srcCompat
is used for integrating vector drawables into your
app.Vector drawables allow you to replace multiple png assets with a
single vector graphic, defined in XML. While previously limited to
Lollipop and higher devices
android:src
Sets a drawable as the content of this ImageView.It will display in
its original size. No automatic scaling .

Replace this:
app:srcCompat="#mipmap/front"
With this:
android:src="#mipmap/front"

app:srcCompat is used to support vector drawables. Ensure that you have added vectorDrawables.useSupportLibrary = true in your build.gradle file
android {
defaultConfig {
vectorDrawables.useSupportLibrary = true
}
}
or you can replace it with android:src=

splashscreen imageview not displaying images

Hi guys i have this splash screen with the layout main.xml which contains an imageview,
here is the main.xml file
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:id="#+id/LinearLayout2"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical" >
<ImageView
android:id="#+id/imageView1"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:src="#drawable/slide11" />
</LinearLayout>
and here is my splashscreen.class file
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
try {
new Handler().postDelayed(new Runnable() {
public void run()
Intent intent = new Intent(getApplicationContext(),content_activity.class);
startActivity(intent);
Main.this.finish(); } }, 5000);
} catch(Exception e){}
}
#Override
public void onBackPressed() {
super.onBackPressed();
} }
when i try to run this in my emulator all works fine, but when i try to run it in a device through debugging mode i don't get the image specified in the imageView, but i get a white screen for the specified amount of time.any help would be much appreciated.
//edit : i double checked the res/drawable folder and i tried primarily using png and also gave a go using .gif none worked in the device. (device micromax a110)

use this instead of your layout.
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:id="#+id/LinearLayout2"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
android:background="#drawable/slide11" >

looks like it was because of the size of the image, when reduced worked !!

Use image as layout background :-
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:id="#+id/LinearLayout2"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
android:background="#drawable/slide11"
>
</LinearLayout>

This can be happening due to issue in the manifest file. Here is an example of my manifest file which has 3 activities and 1 splash screen. Hoping that this helps out.
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.example.foodorder">
<application
android:allowBackup="true"
android:icon="#mipmap/ic_launcher"
android:label="#string/app_name"
android:roundIcon="#mipmap/ic_launcher_round"
android:supportsRtl="true"
android:theme="#style/Theme.FoodOrder">
<activity android:name=".MainActivity"></activity>
<activity android:name=".Final_activity" />
<activity android:name=".Second_activity" />
<activity
android:name=".SplashActivity"
android:exported="true">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
</application>
</manifest>

The emulator isn't showing the XML contents

I have been reading Google's android tutorial and I got a problem... In the tutorial they explain the XML elements (EditText and Button) and in the end they say how to tun the program to see the button + the text field.
The problem is, that the emulator doesn't show them.. just a black screen.
I even tried adding this line to the onCreate function -
System.out.println("Hello World!");
but still the emulator is showing only black screen..
Here's the .java main file - http://pastebin.com/G5J9YjNe
And the XML files (I mentioned what code is what file) - http://pastebin.com/VnRwAfMW
What should I do?
Thanks a lot for everyone who will help!

System.out.println("Hello World!");
does not print any thing on screen. it can seen on Consol. i tried below code and working fine for me.
// Main Activity
public class MainActivity extends Activity {
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.kuchbhi);
System.out.println("Hello World!");
}
Layout /.xml
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="horizontal" >
<EditText android:id="#+id/text_message"
android:layout_weight="1"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:hint="enter text" />
<Button android:layout_height="wrap_content"
android:layout_width="wrap_content"
android:text="Send" />
</LinearLayout>
Manifest file ..
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.test"
android:versionCode="1"
android:versionName="1.0" >
<uses-sdk android:minSdkVersion="8" />
<application
android:icon="#drawable/ic_launcher"
android:label="#string/app_name" >
<activity
android:name="MainActivity"
android:label="#string/app_name" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
</application>
</manifest>
try this code and let me know what u see.
I tried your source code and it is working fine for me. see screen