The icon will change when your app is already running. This menu also appears in the toolbar. Messages that might appear briefly in the status bar Gradle build running Waiting for target device to come on line Installing APK Launching activity Once your app builds and the emulator is ready, Android Studio uploads the app to the emulator and runs it. Step 6: Run your app on a device if you have one What you need: An Android device such as a phone or tablet. A data cable to connect your Android device to your computer via the USB port.
If you are using a Linux or Windows OS, you may need to perform additional steps to run your app on a hardware device. Check the Run Apps on a Hardware Device documentation. On Windows, you may need to install the appropriate USB driver for your device.
Return to the previous screen Settings. Developer options appears at the bottom of the list. Tap Developer options. Enable USB Debugging. Now you can connect your device and run the app from Android Studio. Connect your device to your development machine with a USB cable. On the device, you might need to agree to allow USB debugging from your development device.
In Android Studio, click Run in the toolbar at the top of the window. The Select Deployment Target dialog opens with the list of available emulators and connected devices. Select your device, and click OK. Android Studio installs the app on your device and runs it.
Troubleshooting If you're stuck, quit Android Studio and restart it. If Android Studio does not recognize your device, try the following: Disconnect your device from your development machine and reconnect it.
Restart Android Studio. If your computer still does not find the device or declares it "unauthorized": Disconnect the device. Reconnect the device to your computer. When prompted, grant authorizations.
Step 7: Explore the app template When you created the project and selected Basic Activity , Android Studio set up a number of files, folders, and also user interface elements for you, so you can start out with a working app and major components in place. Task: Explore the layout editor Generally, each screen in your Android app is associated with one or more fragments. What you'll learn How to use the layout editor.
How to set property values. How to add string resources. How to add color resources. On the left is a Palette 1 of views you can add to your app. Try selecting the different modes. Depending on your screen size and work style, you may prefer switching between Code and Design , or staying in Split view. If your Component Tree disappears, hide and show the Palette. Use these buttons to adjust the size of what you see, or click the zoom-to-fit button so that both panels fit on your screen. Practice using the layout menu in the top left of the design toolbar to display the design view, the blueprint view, and both views side by side.
Use the orientation icon to change the orientation of the layout. This allows you to test how your layout will fit portrait and landscape modes. Use the device menu to view the layout on different devices. This is extremely useful for testing! On the right is the Attributes panel. You'll learn about that later. If it's not showing, switch the mode to Design instead of Split or Code. Step 3: Explore view hierarchies In the Component Tree , notice that the root of the view hierarchy is a ConstraintLayout view.
If the code isn't showing, switch to Code or Split view using the icons in the upper right corner. Look at the Attributes panel on the right, and open the Declared Attributes section if needed.
Having the strings in a resource file has several advantages. You can change the value of string without having to change any other code. This simplifies translating your app to other languages, because your translators don't have to know anything about the app code. Run the app to see the change you made in strings. Your app now shows "Hello World! You may need to scroll down to find it. Change some of the text appearance properties.
For example, change the font family, increase the text size, and select bold style. You might need to scroll the panel to see all the fields. Change the text color. Click in the textColor field, and enter g. Below is an example of the textAppearance attributes after making some changes. You see that the new properties have been added. Scroll through the list to get an idea of the attributes you could set for a TextView.
Task: Add color resources So far you have learned how to change property values. What you'll learn How resources are defined. Adding and using color resources. The results of changing layout height and width.
Step 1: Add color resources First, you'll learn how to add new color resources. Add a new property to the TextView called android:background , and start typing to set its value to color.
You can add this property anywhere inside the TextView code. Step 2: Add a new color to use as the screen background color Back in colors. In the Component Tree , select the ConstraintLayout. In the Attributes panel, select the background property and press Enter.
Type "c" in the field that appears. Press Enter to complete the selection. Click on the yellow patch to the left of the color value in the background field. Feel free to change the value of the screenBackground color, but make sure that the final color is noticeably different from the colorPrimary and colorPrimaryDark colors. Step 3: Explore width and height properties Now that you have a new screen background color, you will use it to explore the effects of changing the width and height properties of views.
In the Attributes panel, find and expand the Layout section. Notice that the entire background of the screen uses the screenBackground color. Task: Add views and constraints In this task, you will add two more buttons to your user interface, and update the existing button, as shown below. What you'll learn How to add new views to your layout. How to constrain the position of a view to another view. Step 2: Add buttons and constrain their positions To learn how to use constraints to connect the positions of views to each other, you will add buttons to the layout.
Notice the Palette at the top left of the layout editor. Move the sides if you need to, so that you can see many of the items in the palette. Click on some of the categories, and scroll the listed items if needed to get an idea of what's available.
Select Button , which is near the top, and drag and drop it onto the design view, placing it underneath the TextView near the other button. Step 3: Add a constraint to the new button You will now constrain the top of the button to the bottom of the TextView. Move the cursor over the circle at the top of the Button. Click and drag the circle at the top of the Button onto the circle at the bottom of the TextView.
Take a look at the Constraint Widget in the Layout pane of the Attributes panel. Take a look at the XML code for the button. It now includes the attribute that constrains the top of the button to the bottom of the TextView. To fix this, add a constraint from the left side of the button to the left side of the screen. Also add a constraint to constrain the bottom of the button to the bottom of the screen.
Click on the button you just added in the design layout. Look at the Attributes panel on the right, and notice the id field. Step 4: Adjust the Next button You will adjust the button labeled Next , which Android Studio created for you when you created the project.
To delete a constraint: In the design view or blueprint view, hold the Ctrl key Command on a Mac and move the cursor over the circle for the constraint until the circle highlights, then click the circle. Or click on one of the constrained views, then right-click on the constraint and select Delete from the menu.
Or in the Attributes panel, move the cursor over the circle for the constraint until it shows an x, then click it. If you delete a constraint and want it back, either undo the action, or create a new constraint. Step 5: Delete the chain constraints Click on the Next button, and then delete the constraint from the top of the button to the TextView. Click on the TextView , and then delete the constraint from the bottom of the text to the Next button. Step 6: Add new constraints Constrain the right side of the Next button to the right of the screen if it isn't already.
Delete the constraint on the left side of the Next button. Now constrain the top and bottom of the Next button so that the top of the button is constrained to the bottom of the TextView and the bottom is constrained to the bottom of the screen. The right side of the button is constrained to the right side of the screen. Also constrain the TextView to the bottom of the screen. Your layout should now look something like this. This will make it harder to translate your app to other languages.
To fix this, click the highlighted code. A light bulb appears on the left. Click the lightbulb. In the menu that pops up, select Extract string resource. Step 8: Update the Next button The Next button already has its text in a string resource, but you'll make some changes to the button to match its new role, which will be to generate and display a random number.
If you get a dialog box asking to update all usages of the button, click Yes. This will fix any other references to the button in the project code. In strings. Click Refactor to rename your string and close the dialog. Change the value of the string from Next to Random. Step 9: Add a third button Your final layout will have three buttons, vertically constrained the same, and evenly spaced from each other. Add vertical constraints the same as the other two buttons.
Constrain the top of the third button to the bottom of TextView ; constrain the bottom of the third button to the bottom of the screen. Add horizontal constraints from the third button to the other buttons. Constrain the left side of the third button to the right side of the Toast button; constrain the right side of the third button to the left side of the Random button.
It's OK if you do not see that constraint. Change the text of the TextView to show 0 the number zero. Step Fix errors if necessary The errors occur because the buttons have changed their id and now these constraints are referencing non-existent views. Task: Update the appearance of the buttons and the TextView Your app's layout is now basically complete, but its appearance can be improved with a few small changes.
Step 1: Add new color resources In colors. Add a new color named buttonBackground. Using start and end instead of left and right makes these margins work for all language directions. Step 4: Update the appearance of the TextView Remove the background color of the TextView , either by clearing the value in the Attributes panel or by removing the android:background attribute from the XML code.
Feel free to adjust the value of this constraint as you like. Check in the design view to see how the layout looks. Click and drag the number 50 that appears on the left side, and slide it upwards until it says Step 5: Run your app If you implemented all the updates, your app will look like the following figure. Task: Make your app interactive You have added buttons to your app's main screen, but currently the buttons do nothing.
What you'll learn How to find a view by its ID. How to add click listeners for a view. How to set and get property values of a view from your code. Step 1: Enable auto imports To make your life easier, you can enable auto-imports so that Android Studio automatically imports any classes that are needed by the Java code.
Select Auto Imports. In the Java section, make sure Add Unambiguous Imports on the fly is checked. Step 2: Show a toast In this step, you will attach a Java method to the Toast button to show a toast when the user presses the button. Open FirstFragment. In the body of the click listener, use an action, which in this case is for navigating to another fragment, and navigate there.
Active 1 year, 1 month ago. Viewed 79k times. Improve this question. Agoeng Liu Agoeng Liu 3 3 gold badges 9 9 silver badges 27 27 bronze badges. Java programs run everywhere where the JVM is installed.
However android uses different VM - Dalvik. My guess would be you can do it only through emulator. Add a comment. Active Oldest Votes. Improve this answer. Community Bot 1 1 1 silver badge. Andreas J Andreas J 3 3 silver badges 17 17 bronze badges. I am not sure whether it will work,but just try. Mike Tang Mike Tang 11 4 4 bronze badges. ArshakParsa ArshakParsa 21 3 3 bronze badges. Anish Antony Anish Antony 2 2 gold badges 15 15 silver badges 34 34 bronze badges. In eclipse development you need to develop it as separate java application and build jar and put the jar into your android device.
Himanshu Himanshu 1. Can you give a brief description of how to install at least one? The link isn't guaranteed to always work, which'll make your answer useless in the future — Chris. The link has broken, which makes this a pretty much useless answer. JBED is an. JBED is a java android emulator, by using this application we can install.
Yes, you can do programming on any android phone by using a app name Dcoder. The Android app ecosystem offers a plethora of applications for programming. The Google Play Store is full of apps for all your coding needs — code editors, compilers, and development environments, just to name a few. Yes, you most definitely can code on a phone.
However, the experience will likely be very annoying and overall really not worth it. It gives you arrow keys, ctrl, shift, and all the other keys you will find on a physical keyboard.
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