通过菜单项插入虚拟宠物

app/src/main/java/com/example/pets/CatalogActivity.java

@@ -15,6 +15,7 @@
  */
 package com.example.pets;
 
+import android.content.ContentValues;
 import android.content.Intent;
 import android.database.Cursor;
 import android.database.sqlite.SQLiteDatabase;
@@ -34,6 +35,10 @@
  * Displays list of pets that were entered and stored in the app.
  */
 public class CatalogActivity extends AppCompatActivity {
+    /**
+     * Database helper that will provide us access to the database
+     */
+    private PetDbHelper mDbHelper;
 
     @Override
     protected void onCreate(Bundle savedInstanceState) {
@@ -50,6 +55,10 @@ public void onClick(View view) {
             }
         });
 
+        // To access our database, we instantiate our subclass of SQLiteOpenHelper
+        // and pass the context, which is the current activity.
+        mDbHelper = new PetDbHelper(this);
+
         displayDatabaseInfo();
     }
 
@@ -67,7 +76,8 @@ public boolean onOptionsItemSelected(MenuItem item) {
         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
+                insertPet();
+                displayDatabaseInfo();
                 return true;
             // Respond to a click on the "Delete all entries" menu option
             case R.id.action_delete_all_entries:
@@ -82,10 +92,6 @@ public boolean onOptionsItemSelected(MenuItem item) {
      * the pets database.
      */
     private void displayDatabaseInfo() {
-        // To access our database, we instantiate our subclass of SQLiteOpenHelper
-        // and pass the context, which is the current activity.
-        PetDbHelper mDbHelper = new PetDbHelper(this);
-
         // Create and/or open a database to read from it
         SQLiteDatabase db = mDbHelper.getReadableDatabase();
 
@@ -103,4 +109,29 @@ private void displayDatabaseInfo() {
             cursor.close();
         }
     }
+
+    /**
+     * Helper method to insert hardcoded pet data into the database. For debugging purposes only.
+     */
+    private void insertPet() {
+        // Gets the database in write mode
+        SQLiteDatabase db = mDbHelper.getWritableDatabase();
+
+        // Create a ContentValues object where column names are the keys,
+        // and Toto's pet attributes are the values.
+        ContentValues values = new ContentValues();
+        values.put(PetEntry.COLUMN_PET_NAME, "Toto");
+        values.put(PetEntry.COLUMN_PET_BREED, "Terrier");
+        values.put(PetEntry.COLUMN_PET_GENDER, PetEntry.GENDER_MALE);
+        values.put(PetEntry.COLUMN_PET_WEIGHT, 7);
+
+        // Insert a new row for Toto in the database, returning the ID of that new row.
+        // The first argument for db.insert() is the pets table name.
+        // The second argument provides the name of a column in which the framework
+        // can insert NULL in the event that the ContentValues is empty (if
+        // this is set to "null", then the framework will not insert a row when
+        // there are no values).
+        // The third argument is the ContentValues object containing the info for Toto.
+        long newRowId = db.insert(PetEntry.TABLE_NAME, null, values);
+    }
 }