Finally, we take a look at the --gui command-line option. With this option, we start a graphical shell for our Gradle builds. Until now, we have used the command line to start a task. With the Gradle GUI, we have a graphical overview of the tasks in a project, and we can execute them by simply double-clicking on them.
To start the GUI, we invoke the following command:
hello-world $ gradle --gui
A window is opened with a graphical overview of our task tree. We have only one task, which is listed in the task tree, as shown in the following screenshot:
The output of a running task is shown in the bottom part of the window. When we start the GUI for the first time, the tasks task is executed and we see the output in the window.
The Task Tree tab shows projects and tasks found in our build project. We can execute a task by double-clicking on the task name.
By default all tasks are shown, but we can apply a filter to show or hide certain projects and tasks. The Filter button opens a new dialog window where we can define which tasks and properties are part of the filter. The Toggle filter button makes the filter active or inactive.
We can also right-click on the project and task names. This opens a context menu where we can choose whether to execute the task, add it to the favorites, hide it (adds it to the filter), or edit the build file. If we click on Edit File, and if the .gradle extension is associated with a text editor in our operating system, the editor is opened with the content of the build script. These options can be seen in the following screenshot:
The Favorites tab stores tasks we want to execute regularly. We can add a task by right-clicking on the task in the Task Tree tab and selecting the Add To Favorites menu option. Alternatively, we can open the Favorites tab, click on the Add button and manually enter the project and task name we want to add to our favorites list. We can see the Add Favorite dialog window in the following screenshot:
On the Command Line tab, we can enter any Gradle command we normally would enter on the command prompt. The command can be added to Favorites as well. We can see the Command Line tab contents in the following screenshot:
The last tab is the Setup tab. Here, we can change the project directory, which is set by default to the current directory.
We learned about the different logging levels as command-line options previously in this chapter. In the GUI, we can select the logging level from the Log Level drop-down box with the different log levels. We can choose one of Debug, Info, Lifecyle, and Error as the log levels. The Error log level only shows errors and is the least verbose, while Debug is the most verbose log level. The Lifecyle log level is the default log level.
Here we can also set how detailed the exception stack trace information should be. In the section Stack Trace Output we can choose between the following three options:
- Exceptions only: For showing only exceptions when they occur; this is the default value
- Standard Stack Trace: For showing more stack trace information for the exceptions
- Full Stack Trace: For the most verbose stack trace information for exceptions
If we enable the option Only Show Output When Errors Occur, we get output from the build process only if the build fails; otherwise we don't get any output.
Finally, we can define a different way to start Gradle for the build, with the option Use Custom Gradle Executor . For example, we can define a different batch or script file with extra setup information to run the build process. The following screenshot shows the Setup tab page along with all the options we can set:
