Unable to start activity

[udacity]

Unable to start activity

[PascalProgrammingX]

The error is clearly stated. FloatingActionButton cannot be cast to TextView.

[wdoodoo]

Hello fellow coder,

My coding environment is as follows;
Android Studio 4.2.2
Build #AI-202.7660.26.42.7486908, built on June 24, 2021
Runtime version: 11.0.8+10-b944.6842174 amd64
VM: OpenJDK 64-Bit Server VM by N/A
Windows 10 10.0

1. It seems that you may have not renamed MainActivity to CatalogActivity.

2. In the CatalogActivity (= your MainActivity) please check the below code is present.
   FloatingActionButton fab = (FloatingActionButton) findViewById(R.id.fab);

3. As I am using relatively latest version of coding environment, I had to use below code for the FloatingActionButton in activity_catalog.xml (in your case, activity_main.xml)

<com.google.android.material.floatingactionbutton.FloatingActionButton
android:id="@+id/fab"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentBottom="true"
android:layout_alignParentEnd="true"
android:layout_margin="@dimen/fab_margin"
android:contentDescription="@string/add"
android:src="@drawable/ic_add_pet"/>

I hope this these are helpful.
Happy coding!

Starting code for CatalogActivity.java:
package com.tutorial.android.pets;

import androidx.appcompat.app.AppCompatActivity;

import android.content.Intent;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;

import com.google.android.material.floatingactionbutton.FloatingActionButton;

public class CatalogActivity extends AppCompatActivity {

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_catalog);
    // Setup FAB to open EditorActivity
    FloatingActionButton fab = (FloatingActionButton) findViewById(R.id.fab);
    fab.setOnClickListener(view -> {
        Intent intent = new Intent(CatalogActivity.this, EditorActivity.class);
        startActivity(intent);
    });
}

@Override
public boolean onCreateOptionsMenu(Menu menu) {
    // Inflate the menu options from the res/menu/menu_catalog.xml file.
    // This adds menu items to the app bar.
    getMenuInflater().inflate(R.menu.menu_catalog, menu);
    return true;
}

@Override
public boolean onOptionsItemSelected(MenuItem item) {
    // User clicked on a menu option in the app bar overflow menu
    switch (item.getItemId()) {
        // Respond to a click on the "Insert dummy data" menu option
        case R.id.action_insert_dummy_data:
            // Do nothing for now
            return true;
        // Respond to a click on the "Delete all entries" menu option
        case R.id.action_delete_all_entries:
            // Do nothing for now
            return true;
    }
    return super.onOptionsItemSelected(item);
}

}

And activity_catalog.xml is as below:

<TextView
    android:id="@+id/text_view_pet"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:padding="@dimen/activity_margin"/>

<com.google.android.material.floatingactionbutton.FloatingActionButton
    android:id="@+id/fab"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_alignParentBottom="true"
    android:layout_alignParentEnd="true"
    android:layout_margin="@dimen/fab_margin"
    android:contentDescription="@string/add"
    android:src="@drawable/ic_add_pet"/>

[SudKul]

We have upgraded to code to AndroidX in this commit.

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