测试吧

app/src/main/java/com/example/blu/toys/activity/PlayActivity.java

@@ -190,6 +190,13 @@ public class PlayActivity extends BaseActivity {
 		startActivity(intent);
 	}
 
+	@Override
+	public void onBackPressed() {
+		timerManager.cancelTimer();
+		Intent intent = new Intent(PlayActivity.this, SetTimeActivity.class);
+
+		startActivity(intent);
+	}
 	@OnClick({R.id.cancel_but, R.id.pause_but, R.id.resume_but})
 	public void onViewClicked(View view) {
 		SpUtils spUtils = SpUtils.getSpUtils(PlayActivity.this);

app/src/main/java/com/example/blu/toys/activity/SearchingActivity.java

@@ -48,4 +48,9 @@ public class SearchingActivity extends BaseActivity {
 	public void onViewClicked() {
 		finish();
 	}
+
+	@Override
+	public void onBackPressed() {
+		finish();
+	}
 }
\ No newline at end of file

app/src/main/java/com/example/blu/toys/activity/SelectDeviceActivity.java

@@ -90,4 +90,11 @@ public class SelectDeviceActivity extends BaseActivity {
 
 		startActivity(intent);
 	}
+
+	@Override
+	public void onBackPressed() {
+		Intent intent = new Intent(SelectDeviceActivity.this, AddDeviceActivity.class);
+
+		startActivity(intent);
+	}
 }
\ No newline at end of file

app/src/main/java/com/example/blu/toys/activity/SetTimeActivity.java

@@ -363,6 +363,14 @@ public class SetTimeActivity extends BaseActivity {
 		startActivity(intent);
 	}
 
+	@Override
+	public void onBackPressed() {
+		BlePlay.getInstance().closeBle();
+		Intent intent = new Intent(SetTimeActivity.this, SelectDeviceActivity.class);
+
+		startActivity(intent);
+	}
+
 
 	@OnClick({R.id.back_but, R.id.start_but})
 	public void onViewClicked(View view) {

app/src/main/java/com/example/blu/toys/activity/TimerManager.java

 package com.example.blu.toys.activity;
-
 import android.os.Handler;
 import android.os.Message;
-
 import com.blankj.utilcode.util.LogUtils;
-
-
 import java.util.Timer;
 import java.util.TimerTask;
 

app/src/main/res/layout/activity_searching.xml

@@ -38,7 +38,7 @@
 		android:layout_centerHorizontal="true"
 		android:layout_marginTop="@dimen/dp_14"
 		android:gravity="center"
-		android:text="Will search for the STLGL TIMER"
+		android:text=""
 		android:textColor="#E07A3A"
 		android:textSize="@dimen/sp_16" />
 
@@ -50,7 +50,7 @@
 		android:layout_marginLeft="@dimen/dp_40"
 		android:layout_marginTop="@dimen/dp_14"
 		android:gravity="center"
-		android:text="Animate Bee to fly around while waiting"
+		android:text=""
 		android:textColor="#E07A3A"
 		android:textSize="@dimen/sp_16" />
 

app/src/main/res/layout/activity_seleclt_device.xml

@@ -66,7 +66,7 @@
 			android:layout_gravity="center_horizontal"
 			android:layout_marginTop="@dimen/dp_14"
 			android:gravity="center"
-			android:text="Option Do we want to allow multiple devices?"
+			android:text="device not found"
 			android:textColor="#E07A3A"
 			android:textSize="@dimen/sp_14" />