Cannot Start New Intent By Setclassname With Different Package In Android

I want to start a new Intent dynamically. Therefore setClassName seems the best choice. First, I define 3 activity in Manifest

Solution 1:

setClassName take a Package Context as first param setClassName(Context packageContext, String className):

Intentintent=newIntent();
if(index == 0) {
  intent.setClassName("com.example.pkg1", "com.example.pkg1.Act1");
} else {
  intent.setClassName("com.example.pkg1", "com.example.pkg1.Act2");
  startActivity(intent);
}

and in

<activityandroid:name="com.example.pkg2.Act" /><activityandroid:name="com.example.pkg1.Act1" /><activityandroid:name="com.example.pkg1.Act2" />

or you try this :

if(index == 0) {
  Intentintent=newIntent(Intent.ACTION_MAIN)
    .addCategory(intent.CATEGORY_LAUNCHER)
    .setClassName("com.example.pkg1", "com.example.pkg1.Act1")
    .addFlags(Intent.FLAG_ACTIVITY_NEW_TASK)
    .addFlags(Intent.FLAG_FROM_BACKGROUND)
    .setComponent(newComponentName("com.example.pkg1", "com.example.pkg1.Act1"));
  getApplicationContext().startActivity(intent);
} else {
  Intentintent=newIntent(Intent.ACTION_MAIN)
    .addCategory(intent.CATEGORY_LAUNCHER)
    .setClassName("com.example.pkg1", "com.example.pkg1.Act2")
    .addFlags(Intent.FLAG_ACTIVITY_NEW_TASK)
    .addFlags(Intent.FLAG_FROM_BACKGROUND)
    .setComponent(newComponentName("com.example.pkg1", "com.example.pkg1.Act2"));
  getApplicationContext().startActivity(intent);
}

Solution 2:

The first param is the applicationId located in the build.gradle file

The second param is full path to of the class with its package. for example: intentObj.setClassName("applicatioId", "com.youCompany.yourAppName.YourClassName")

Solution 3:

You can also launch Activities in this manner. Try this

Intentintent=newIntent();
Class<?> activityClass = Class.forName("your.application.package.name." + NameOfClassToOpen); 
intent.setClass(this, activityClass);

And in order to use setClassName. You should supply it with packageName and its class path too like

intent.setClassName("your.application.package.name", "your.application.package.name.activityClass");

Solution 4:

Follow the syntax to write setClassName() method:

setClassName( pkgName, className ) 

Solution 5:

You can use the following method to create the intent in the package context:

    Intent intent = newIntent(this, MyActivity.class);
    intent.setAction(Intent.ACTION_VIEW);
    intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
    startActivity(intent);

This way you keep on generic code.

HTH