# Selecting Objects

## Selection Introduction

Selecting objects is probably the most frequently task when using Dia. From the moment you create a new object to the moment you think the diagram looks the way it should be, you will always have to select objects to set them up properly.

When you select objects, you bring focus to an object to edit. An object which is not selected, cannot be edited.

Selecting objects can be done in many different ways, and there are also many operations can be performed on these selected objects.

You can select objects to simply drag them around the diagram, or to group them in a logical way to manipulate them more easily, to connect them each others, or to simply remove them from the diagram.

## How To Select Objects

### Basic Selection

The basic way to select an object is by clicking on it.

When the object is selected it appears on the diagram with some little green points on its corners and on its sides.

Once the green points appeared, you can start manipulate this object as you wish. When you're done with it you can deselect this object by clicking on any free space of the diagram, the green points will desappear and selection of an other object becomes possible.

### Multiple Selection

The simplest way to select more than one object at the time, is by clicking on a free space of the diagram with the left mouse button and moving the mouse while pressing on it. Doing so will draw a thin rectangle on the Canvas. All objects present in this area will be selected when depressing the button.

An other way to do so is by holding down the Shift key while selecting the objects by clicking them one by one.

Once your selection is complete, each of the selected objects must appear with its own green points as described above.

Multiple selection is useful when you want apply the same operation on many different objects and you don't want waste time by selecting them one by one.

When selected, objects act like a group. Meaning if you try to drag one of them, it is the whole group which moves. The same if you try to delete one of them, it is the whole group will be removed from the diagram.

Then if you click on any free space on the diagram or if you change to another layer, you will loose the selection. Or if you want to add some more objects to your selection, simply hold down the Shift key again and click on the items you want add.

Assuming you selected some objects on your diagram, it is still possible to resize one of them without changing the size or position of other selected objects. To learn how to resize objects see the Resizing Objects section.

### Other Ways for Selecting Objects

Other ways for selecting objects are describe below, all these options can be reached in the Main Popup Menu under the Select menu :

Selecting all objects

  Choosing the All option will let you select all the objects present on the current layer, the same way as you could do it by hand.

  This option is a shortcut of when your diagram contains a lot of objects and you don't want waste your time in selecting objects one by one.

Deselecting all objects

  Selecting the None option will deselect objects you have selected before. It has the same effect as when you clicking on any free part of your diagram.

  After you have deselected objects you cannot perform any operation on them anymore. So you have to select them again to continue

  Often you will have to keep your selections persistent, to do so, you can form an arbitrary group with the selected items or cut and paste them in a new layer which will contain all the objects of your selection.

Inverting the selection

  Admiting you have ten items on your diagram and want to select only eight of them. One way to select these eight objects can be done by the Invert option under the Select menu.

  Simply select by hand the two objects you don't need, then check the Invert option and you will get the eight objects you wanted being selected and the two others left on their owns.

  Another way to do this is to select All the items as described above, and then press the Shift key and deselect the objects you don't need.

  Only objects present in the current layer can be selected. If an object doesn't want to be select it's probably because it is situated in another layer. To know how to change the current layer or how to manipulate many layers, please refer to the Managing Layers section.

### Selecting Connected Objects

One really useful and powerful feature of Dia is its ability of handling connection between objects.

Connections, in Dia, can be used for many purposes. The first, and not the least, is to explicitly specify a direct relationship between two objects.

The second could be it is easier to manage objects that behave efficiently in following established rules and can be accessed in a few clicks.

Selecting objects connected to a particular object, is as simple than selecting this particular object, right click on the Canvas to get the Main Popup Menu appear and click on the Select Connected button.

If this object doesn't have any object connected to it, it will do nothing. Otherwise, all the connected objects will be magicaly selected and will form a new group of temporary selected objects.

If you repeat this manipulation again, that will be all the connected objects to this new group that will be add to the selection.

You can redo the operation until you have selected all objects that were connected all together.

### Selecting Transitive Objects

Technic shown above is fine when you only want select a small number of connected objects at the time.

Sometimes you will have to select a whole bunch of objects which are connected all together. This way of selecting objects step by step isn't efficient.

This is the reason why Dia offers you to do all these steps at once.

To do so, select the root object you desire, then right click on the Canvas to have the Main Popup Menu appear on screen, but this time choose the Select Transitive button instead of Connected.

And that's it, all objects that were connected to the root object you choose are now selected and ready to be manipulate and waiting for you to apply on them any number of operations you would like.

### Selecting Same Type of Objects

Dia implements some trick to select objects issued from the same type.

Meaning if, for any reason, you need to select objects matching the same type (all Rectangles, Lines or any custom Shape) you could do it by selecting an object of the type you need to select and click, in the Main Popup Menu, the Select Same Type button.

This will automaticaly select all objects which correspond to the type you have chosen. Only objects present in the current layer will be selected.