Dashboard chart - show last seven days by default

Question

Magento admin dashboard chart shows last 24 hours stats by default.

How to show last 7 days by default instead?

Is this possible without overriding core files?

Answer 1

You need to rewrite the method Mage_Adminhtml_Block_Dashboard_Graph::_prepareData.
by default it looks like this:

protected function _prepareData()
{
    $availablePeriods = array_keys($this->helper('adminhtml/dashboard_data')->getDatePeriods());
    $period = $this->getRequest()->getParam('period');
    $this->getDataHelper()->setParam('period',
        ($period && in_array($period, $availablePeriods)) ? $period : '24h'
    );
}

You need to replace 24h with 7d.